diff --git a/dev/fluids/Acetone.json b/dev/fluids/Acetone.json
index 52eaebbc..aede19b0 100644
--- a/dev/fluids/Acetone.json
+++ b/dev/fluids/Acetone.json
@@ -373,22 +373,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 508.1, 
-        "T_min": 508.09697325761744, 
+        "T_min": 508.09970264118135, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -1.5123933548972854e-11, 
-          -1.7185082712306687e-08, 
-          0.0011638028537861549, 
-          504.579957217175
+          0.0, 
+          0.0, 
+          -7.911681289094714e-06, 
+          508.1371849020588
         ], 
         "cV": [
-          1.9536072269032177e-10, 
-          -2.983480058312324e-06, 
-          0.015098157455448244, 
-          482.76079813563524
+          0.0, 
+          0.0, 
+          8.31994940245324e-06, 
+          508.0608962378085
         ], 
-        "rhomolar_max": 4814.181193727979, 
-        "rhomolar_min": 4590.050467927069
+        "rhomolar_max": 4737.584782275033, 
+        "rhomolar_min": 4664.2595400179
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Argon.json b/dev/fluids/Argon.json
index b8bcb7e1..f5583011 100644
--- a/dev/fluids/Argon.json
+++ b/dev/fluids/Argon.json
@@ -526,22 +526,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 150.687, 
-        "T_min": 150.68697834063298, 
+        "T_min": 150.68698169043714, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -6.171554333557227e-07, 
-          150.69527446806111
+          -5.509866301146546e-07, 
+          150.69438731448608
         ], 
         "cV": [
           0.0, 
           0.0, 
-          6.072607995401675e-07, 
-          150.67885819354578
+          5.667184337162037e-07, 
+          150.67940176246375
         ], 
-        "rhomolar_max": 13442.525139946354, 
-        "rhomolar_min": 13371.76233564158
+        "rhomolar_max": 13440.660161575233, 
+        "rhomolar_min": 13375.121616690334
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/D4.json b/dev/fluids/D4.json
index 65e80ec0..9198b258 100644
--- a/dev/fluids/D4.json
+++ b/dev/fluids/D4.json
@@ -381,22 +381,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 586.5, 
-        "T_min": 583.1872205036263, 
+        "T_min": 585.8223731516954, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
-          -1.667552305553379e-05, 
-          0.034382527265190706, 
-          568.7770449657756
+          -7.862666279638519e-06, 
+          0.016211685644670307, 
+          578.1434596708557
         ], 
         "cV": [
-          6.813459579816792e-08, 
-          -0.00021263235123370055, 
-          0.22117438047692597, 
-          509.81953537332856
+          6.746394257626074e-08, 
+          -0.00021062780266197875, 
+          0.2191796259421155, 
+          510.4803477882244
         ], 
-        "rhomolar_max": 1476.6422633230486, 
-        "rhomolar_min": 675.0371135400856
+        "rhomolar_max": 1324.4971267138706, 
+        "rhomolar_min": 824.503552249034
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/D6.json b/dev/fluids/D6.json
index 0b0d9ff2..a54b521d 100644
--- a/dev/fluids/D6.json
+++ b/dev/fluids/D6.json
@@ -372,22 +372,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 645.78, 
-        "T_min": 645.4997615767367, 
+        "T_min": 645.5612757191427, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -1.554702914197144e-07, 
-          0.00027871311312902783, 
-          -0.16613864293822964, 
-          678.7008854032358
+          -1.198196800754583e-07, 
+          0.00020830049432842273, 
+          -0.11988515995442227, 
+          668.5936073909794
         ], 
         "cV": [
-          2.1732433324774884e-07, 
-          -0.00042927603672073575, 
-          0.28201442644063596, 
-          584.1491278422845
+          1.7569888176414546e-07, 
+          -0.00035430081210555803, 
+          0.23708993877492088, 
+          593.1021821692563
         ], 
-        "rhomolar_max": 725.3981107757561, 
-        "rhomolar_min": 542.276230072255
+        "rhomolar_max": 715.9728372726955, 
+        "rhomolar_min": 550.5496590706158
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Deuterium.json b/dev/fluids/Deuterium.json
index c301671a..71c9e07d 100644
--- a/dev/fluids/Deuterium.json
+++ b/dev/fluids/Deuterium.json
@@ -460,22 +460,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 38.34, 
-        "T_min": 38.3399506598222, 
+        "T_min": 38.3393455081093, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -8.339819490855398e-07, 
-          38.35436950898275
+          -3.0138638445784953e-06, 
+          38.391928874042094
         ], 
         "cV": [
           0.0, 
           0.0, 
-          8.380089288669903e-07, 
-          38.325561106155625
+          3.024694971483841e-06, 
+          38.28788450564134
         ], 
-        "rhomolar_max": 17289.162165151512, 
-        "rhomolar_min": 17171.122133543762
+        "rhomolar_max": 17447.160404205744, 
+        "rhomolar_min": 17013.617225249614
       }, 
       "gas_constant": 8.3144621, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/DimethylEther.json b/dev/fluids/DimethylEther.json
index 5d9422c7..e935a8c0 100644
--- a/dev/fluids/DimethylEther.json
+++ b/dev/fluids/DimethylEther.json
@@ -410,22 +410,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 400.378, 
-        "T_min": 400.3774167354802, 
+        "T_min": 400.37798307940494, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -1.846177917829548e-05, 
-          400.48766296831906
+          -2.7743113901126396e-06, 
+          400.39447940965727
         ], 
         "cV": [
           0.0, 
           0.0, 
-          1.8536722158567707e-05, 
-          400.2678918703781
+          3.1494540868192204e-06, 
+          400.3592922427243
         ], 
-        "rhomolar_max": 5971.593082884313, 
-        "rhomolar_min": 5908.534646267459
+        "rhomolar_max": 5946.0990251903795, 
+        "rhomolar_min": 5934.627451427649
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Ethanol.json b/dev/fluids/Ethanol.json
index 7116039d..4de556e6 100644
--- a/dev/fluids/Ethanol.json
+++ b/dev/fluids/Ethanol.json
@@ -479,22 +479,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 514.71, 
-        "T_min": 513.7464813947397, 
+        "T_min": 514.622869613147, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          1.0321929712568178e-10, 
-          -2.8791135673288862e-06, 
-          0.023257198124035903, 
-          456.514456977566
+          -4.321404777621795e-11, 
+          -1.7076779247457985e-07, 
+          0.006584159024686301, 
+          490.68230210427
         ], 
         "cV": [
-          -2.567634017795019e-10, 
-          3.6513286874767864e-06, 
-          -0.016217580191766636, 
-          536.0239643040333
+          -2.864544233706444e-10, 
+          4.144580667152323e-06, 
+          -0.01893530325526736, 
+          540.986310635042
         ], 
-        "rhomolar_max": 6943.380770596912, 
-        "rhomolar_min": 4649.622177033432
+        "rhomolar_max": 6232.430871796149, 
+        "rhomolar_min": 5611.7525953516915
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/HFE143m.json b/dev/fluids/HFE143m.json
index 85cce98c..a60bd4cd 100644
--- a/dev/fluids/HFE143m.json
+++ b/dev/fluids/HFE143m.json
@@ -382,22 +382,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 377.921, 
-        "T_min": 377.88522000242136, 
+        "T_min": 377.88975653726936, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          4.9355266611563965e-11, 
-          -1.1363349519029853e-06, 
-          0.00736469652648742, 
-          363.2831553274167
+          1.2548213865690152e-10, 
+          -2.2189763500125694e-06, 
+          0.012495023999688158, 
+          355.1823983329997
         ], 
         "cV": [
-          -1.6224665103344288e-10, 
-          1.8467354481248633e-06, 
-          -0.0066516525010036605, 
-          385.2331741502011
+          -2.2818544758356846e-10, 
+          2.7463251549141047e-06, 
+          -0.010740626529167381, 
+          391.42531644901993
         ], 
-        "rhomolar_max": 4935.29110614525, 
-        "rhomolar_min": 4335.002308503029
+        "rhomolar_max": 4915.958005243979, 
+        "rhomolar_min": 4357.2413514049285
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Helium.json b/dev/fluids/Helium.json
index 1749c9d8..3c0a8384 100644
--- a/dev/fluids/Helium.json
+++ b/dev/fluids/Helium.json
@@ -460,22 +460,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 5.1953000000000005, 
-        "T_min": 5.19073171770731, 
+        "T_min": 5.19520893622453, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -3.0333435224167437e-13, 
-          1.5607506016709e-08, 
-          -0.00026681298442982895, 
-          6.710133323667334
+          0.0, 
+          0.0, 
+          9.016064727014562e-07, 
+          5.178953874649923
         ], 
         "cV": [
           0.0, 
-          -4.479989405503328e-10, 
-          1.624444158435496e-05, 
-          5.048044137037824
+          0.0, 
+          6.815469697713246e-08, 
+          5.194064355343805
         ], 
-        "rhomolar_max": 19915.76431162559, 
-        "rhomolar_min": 14936.712852945791
+        "rhomolar_max": 18028.998312203898, 
+        "rhomolar_min": 16793.866475690647
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Hydrogen.json b/dev/fluids/Hydrogen.json
index 71d46d90..36cbc989 100644
--- a/dev/fluids/Hydrogen.json
+++ b/dev/fluids/Hydrogen.json
@@ -432,22 +432,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 33.145, 
-        "T_min": 33.13810506132737, 
+        "T_min": 33.140418136928176, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          3.1007578284721566e-12, 
-          -1.5869880447859634e-07, 
-          0.0026850233556669507, 
-          18.107690278950276
+          6.430433928390398e-12, 
+          -3.15824835274259e-07, 
+          0.005156102359493002, 
+          5.156196888181069
         ], 
         "cV": [
-          -2.3396699485553584e-12, 
-          9.516798742074658e-08, 
-          -0.0012636720187622463, 
-          38.58044486815464
+          -5.225396958873852e-12, 
+          2.274807134854265e-07, 
+          -0.0032854482527420407, 
+          48.87593060548779
         ], 
-        "rhomolar_max": 16262.923237049079, 
-        "rhomolar_min": 14746.877675758724
+        "rhomolar_max": 16106.075389591539, 
+        "rhomolar_min": 14901.511073260717
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/IsoButane.json b/dev/fluids/IsoButane.json
index 98f01c66..4f0d3de7 100644
--- a/dev/fluids/IsoButane.json
+++ b/dev/fluids/IsoButane.json
@@ -475,22 +475,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 407.817, 
-        "T_min": 407.73549293470376, 
+        "T_min": 407.75175593000233, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -5.728389280296945e-10, 
-          6.296755366265217e-06, 
-          -0.022991762972926447, 
-          435.69130219666266
+          -4.4074892731107477e-10, 
+          4.7123672337356735e-06, 
+          -0.01666254100244952, 
+          427.2704151083339
         ], 
         "cV": [
-          5.562666408422913e-10, 
-          -6.761233991678565e-06, 
-          0.027344254864717768, 
-          371.015481302833
+          4.1509787184030793e-10, 
+          -5.1719952249655754e-06, 
+          0.021387369158083452, 
+          378.44898088210823
         ], 
-        "rhomolar_max": 4253.160501655689, 
-        "rhomolar_min": 3479.687062549918
+        "rhomolar_max": 4218.938217762173, 
+        "rhomolar_min": 3515.5103304226764
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/IsoButene.json b/dev/fluids/IsoButene.json
index a64cb089..97b9ea53 100644
--- a/dev/fluids/IsoButene.json
+++ b/dev/fluids/IsoButene.json
@@ -370,22 +370,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 418.09000000000003, 
-        "T_min": 418.08543171770737, 
+        "T_min": 418.08950991019015, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          1.0856405178489673e-09, 
-          -1.4451084442137125e-05, 
-          0.06388776104495195, 
-          324.24484504699296
+          0.0, 
+          0.0, 
+          -2.3926474256584434e-05, 
+          418.18977339765
         ], 
         "cV": [
-          -6.230035048466998e-10, 
-          6.9227418610441575e-06, 
-          -0.02523563018482191, 
-          448.11876326463465
+          0.0, 
+          0.0, 
+          2.5211881942311312e-05, 
+          417.9848664523006
         ], 
-        "rhomolar_max": 4246.188019158735, 
-        "rhomolar_min": 4095.5716752458243
+        "rhomolar_max": 4190.48316039618, 
+        "rhomolar_min": 4150.5611571944355
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Krypton.json b/dev/fluids/Krypton.json
index 37121bf5..1a994976 100644
--- a/dev/fluids/Krypton.json
+++ b/dev/fluids/Krypton.json
@@ -369,22 +369,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 209.48000000000002, 
-        "T_min": 209.47310506132737, 
+        "T_min": 209.4785594520556, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          6.390300964893231e-11, 
-          -2.199509680360674e-06, 
-          0.02516089390363733, 
-          113.79346021244321
+          7.439981467718757e-10, 
+          -2.4434077759864862e-05, 
+          0.26746352188901107, 
+          -766.3592353019499
         ], 
         "cV": [
-          -3.436623953002642e-11, 
-          1.0066209446840255e-06, 
-          -0.009706635600422744, 
-          240.19068612286947
+          -7.492939677469447e-10, 
+          2.417791448185612e-05, 
+          -0.2600344669020087, 
+          1141.6344647277606
         ], 
-        "rhomolar_max": 11108.82129459245, 
-        "rhomolar_min": 10591.412518037536
+        "rhomolar_max": 10950.720003147018, 
+        "rhomolar_min": 10746.269399995741
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/MD3M.json b/dev/fluids/MD3M.json
index 32fbba67..0c742ea7 100644
--- a/dev/fluids/MD3M.json
+++ b/dev/fluids/MD3M.json
@@ -364,22 +364,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 628.36, 
-        "T_min": 628.3495934234678, 
+        "T_min": 628.3569917799531, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          7.278401833841499e-08, 
-          -0.00016564557063869183, 
-          0.12450370964999923, 
-          597.405816117967
+          3.306215390839023e-07, 
+          -0.0007009970408251223, 
+          0.49499207140405216, 
+          511.9476683657978
         ], 
         "cV": [
-          4.6976897100679125e-08, 
-          -0.00011341900983330957, 
-          0.08928269840896542, 
-          605.3211026107697
+          -3.977392516737338e-07, 
+          0.0007943503177039177, 
+          -0.528334852377581, 
+          745.381333245749
         ], 
-        "rhomolar_max": 713.1509447889869, 
-        "rhomolar_min": 661.6875900836687
+        "rhomolar_max": 699.3896862967481, 
+        "rhomolar_min": 673.1968167336198
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/MM.json b/dev/fluids/MM.json
index aca95330..dd3a8d64 100644
--- a/dev/fluids/MM.json
+++ b/dev/fluids/MM.json
@@ -430,6 +430,25 @@
           "type": "ResidualHelmholtzGaussian"
         }
       ], 
+      "critical_region_splines": {
+        "T_max": 518.75, 
+        "T_min": 518.2425865117793, 
+        "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
+        "cL": [
+          -7.204081377481409e-09, 
+          3.2242768485801064e-05, 
+          -0.04789483097662979, 
+          542.3479328063715
+        ], 
+        "cV": [
+          -2.379131509735468e-08, 
+          9.657118716867812e-05, 
+          -0.12666182160274833, 
+          571.6341272287368
+        ], 
+        "rhomolar_max": 1924.5652666485823, 
+        "rhomolar_min": 1384.2860882387943
+      }, 
       "gas_constant": 8.3144621, 
       "gas_constant_units": "J/mol/K", 
       "molar_mass": 0.16237752, 
diff --git a/dev/fluids/MethylStearate.json b/dev/fluids/MethylStearate.json
index 7b41ddfc..ee31d942 100644
--- a/dev/fluids/MethylStearate.json
+++ b/dev/fluids/MethylStearate.json
@@ -416,22 +416,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 775.0, 
-        "T_min": 774.9931050613274, 
+        "T_min": 774.9998288233945, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          3.695594514041921e-08, 
-          -0.00015314359180175198, 
-          0.1733360078297273, 
-          715.4195409309607
+          0.0, 
+          0.0, 
+          -0.00010980425210695775, 
+          775.0872175174486
         ], 
         "cV": [
-          -8.410775169091402e-09, 
-          -4.503043200679788e-05, 
-          0.08745473360028402, 
-          738.1598907285911
+          0.0, 
+          0.0, 
+          0.00010988357503613521, 
+          774.9127194763488
         ], 
-        "rhomolar_max": 804.623188217212, 
-        "rhomolar_min": 783.9995580899517
+        "rhomolar_max": 795.8589251075718, 
+        "rhomolar_min": 792.7422002522696
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Neon.json b/dev/fluids/Neon.json
index fdb7880b..fa12a422 100644
--- a/dev/fluids/Neon.json
+++ b/dev/fluids/Neon.json
@@ -447,22 +447,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 44.491800000000005, 
-        "T_min": 44.49141355465158, 
+        "T_min": 44.491722228412755, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -1.5811616648711508e-06, 
-          44.52956130288046
+          -7.086502874109214e-07, 
+          44.50872398616395
         ], 
         "cV": [
           0.0, 
           0.0, 
-          1.5834258838542428e-06, 
-          44.4539846230418
+          7.097427124728881e-07, 
+          44.47484992454073
         ], 
-        "rhomolar_max": 24126.40596873362, 
-        "rhomolar_min": 23637.943519451463
+        "rhomolar_max": 23991.746074516006, 
+        "rhomolar_min": 23772.422844948775
       }, 
       "gas_constant": 8.31434, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Neopentane.json b/dev/fluids/Neopentane.json
index 952b01ed..6cfbcb22 100644
--- a/dev/fluids/Neopentane.json
+++ b/dev/fluids/Neopentane.json
@@ -369,22 +369,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 433.74, 
-        "T_min": 433.73543171770734, 
+        "T_min": 433.7374308769143, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          1.8157110662036835e-09, 
-          -1.8874192929720874e-05, 
-          0.0651915711809464, 
-          358.895660684941
+          3.5552432643477683e-09, 
+          -3.6044510806120894e-05, 
+          0.12168351856799782, 
+          296.9433793880215
         ], 
         "cV": [
-          -2.2365486585331262e-09, 
-          2.089693784319932e-05, 
-          -0.06492040004203695, 
-          500.7835165371252
+          -5.6898059160504035e-09, 
+          5.456581605156137e-05, 
+          -0.1743388599380053, 
+          619.3097765122714
         ], 
-        "rhomolar_max": 3339.892894257803, 
-        "rhomolar_min": 3198.06041887194
+        "rhomolar_max": 3321.0423374845595, 
+        "rhomolar_min": 3218.167274770953
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Nitrogen.json b/dev/fluids/Nitrogen.json
index 009222cf..64201790 100644
--- a/dev/fluids/Nitrogen.json
+++ b/dev/fluids/Nitrogen.json
@@ -521,22 +521,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 126.19200000000001, 
-        "T_min": 126.19199998688855, 
+        "T_min": 126.19197283625158, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -1.547800694886972e-07, 
-          126.19373104504585
+          -3.8150408064612515e-07, 
+          126.1962667040463
         ], 
         "cV": [
           0.0, 
           0.0, 
-          9.95463660457675e-10, 
-          126.19198886683252
+          7.925054408276641e-07, 
+          126.18313669723965
         ], 
-        "rhomolar_max": 11183.986174852074, 
-        "rhomolar_min": 11170.73026187868
+        "rhomolar_max": 11255.103189047548, 
+        "rhomolar_min": 11149.625676641272
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/OrthoDeuterium.json b/dev/fluids/OrthoDeuterium.json
index 84f8db33..b636ee6d 100644
--- a/dev/fluids/OrthoDeuterium.json
+++ b/dev/fluids/OrthoDeuterium.json
@@ -437,22 +437,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 38.34, 
-        "T_min": 38.33996730937413, 
+        "T_min": 38.3396608555373, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -6.850188755192064e-07, 
-          38.3518028752252
+          -2.174063770932284e-06, 
+          38.37745911877317
         ], 
         "cV": [
           0.0, 
           0.0, 
-          6.843466890793785e-07, 
-          38.328208706547166
+          2.1783706563740146e-06, 
+          38.30246667359068
         ], 
-        "rhomolar_max": 17277.722226405003, 
-        "rhomolar_min": 17182.23089934681
+        "rhomolar_max": 17385.995636942647, 
+        "rhomolar_min": 17074.312784095087
       }, 
       "gas_constant": 8.3144621, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/OrthoHydrogen.json b/dev/fluids/OrthoHydrogen.json
index a9db7423..45874a4c 100644
--- a/dev/fluids/OrthoHydrogen.json
+++ b/dev/fluids/OrthoHydrogen.json
@@ -400,22 +400,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 33.22, 
-        "T_min": 33.216973257617425, 
+        "T_min": 33.21859684084077, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          4.066468806855226e-12, 
-          -2.0485786362827496e-07, 
-          0.003417899984425546, 
-          14.316580566669387
+          1.4231762427055805e-11, 
+          -6.794822502274015e-07, 
+          0.01080431180609879, 
+          -23.99858599834753
         ], 
         "cV": [
-          -3.379814959674437e-12, 
-          1.404217131242082e-07, 
-          -0.0019188970430762365, 
-          41.812545688089735
+          -1.3076458482547849e-11, 
+          5.86239854331421e-07, 
+          -0.008750877129877292, 
+          76.70950470337729
         ], 
-        "rhomolar_max": 15899.98591137461, 
-        "rhomolar_min": 14989.857909343546
+        "rhomolar_max": 15742.198240172262, 
+        "rhomolar_min": 15145.91854837676
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/ParaDeuterium.json b/dev/fluids/ParaDeuterium.json
index 26377611..c6c1db34 100644
--- a/dev/fluids/ParaDeuterium.json
+++ b/dev/fluids/ParaDeuterium.json
@@ -435,22 +435,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 38.34, 
-        "T_min": 38.33996730937413, 
+        "T_min": 38.33992222841275, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -6.849502299785245e-07, 
-          38.35180169246253
+          -1.0134264329467987e-06, 
+          38.35746133743967
         ], 
         "cV": [
           0.0, 
           0.0, 
-          6.848389037037868e-07, 
-          38.32820022568919
+          1.0488475637710707e-06, 
+          38.32192835647623
         ], 
-        "rhomolar_max": 17277.727009113827, 
-        "rhomolar_min": 17182.26523245882
+        "rhomolar_max": 17306.741226317383, 
+        "rhomolar_min": 17155.850438196074
       }, 
       "gas_constant": 8.3144621, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Propylene.json b/dev/fluids/Propylene.json
index f69afa2c..2684ee11 100644
--- a/dev/fluids/Propylene.json
+++ b/dev/fluids/Propylene.json
@@ -479,22 +479,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 364.211, 
-        "T_min": 364.21041673548024, 
+        "T_min": 364.21077733486237, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -6.505035916897591e-06, 
-          364.2464979809985
+          -3.6652101077273866e-06, 
+          364.2310010515579
         ], 
         "cV": [
           0.0, 
           0.0, 
-          6.4811926293276935e-06, 
-          364.17563213182177
+          3.951799999729862e-06, 
+          364.1894350274015
         ], 
-        "rhomolar_max": 5546.663535640788, 
-        "rhomolar_min": 5367.006606323258
+        "rhomolar_max": 5517.750988646923, 
+        "rhomolar_min": 5400.654755394478
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R11.json b/dev/fluids/R11.json
index 52a22fec..8140fbb0 100644
--- a/dev/fluids/R11.json
+++ b/dev/fluids/R11.json
@@ -455,6 +455,25 @@
           "type": "ResidualHelmholtzPower"
         }
       ], 
+      "critical_region_splines": {
+        "T_max": 471.06, 
+        "T_min": 471.059233646828, 
+        "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
+        "cL": [
+          0.0, 
+          0.0, 
+          -4.043954354486559e-06, 
+          471.07663294370076
+        ], 
+        "cV": [
+          0.0, 
+          0.0, 
+          2.3593786652777144e-06, 
+          471.05029578252663
+        ], 
+        "rhomolar_max": 4302.545317673531, 
+        "rhomolar_min": 3788.227991064693
+      }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
       "molar_mass": 0.137368, 
diff --git a/dev/fluids/R113.json b/dev/fluids/R113.json
index f159c6e9..5a5f7f8f 100644
--- a/dev/fluids/R113.json
+++ b/dev/fluids/R113.json
@@ -396,22 +396,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 487.21000000000004, 
-        "T_min": 487.20941673548026, 
+        "T_min": 487.2099540373214, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -2.1155772356204888e-05, 
-          487.27322739169836
+          -5.934357667529962e-06, 
+          487.22773577208176
         ], 
         "cV": [
           0.0, 
           0.0, 
-          2.1763182218616364e-05, 
-          487.1449572672853
+          6.04290259183351e-06, 
+          487.19193982414185
         ], 
-        "rhomolar_max": 3016.2291002048787, 
-        "rhomolar_min": 2961.858589771953
+        "rhomolar_max": 2996.404287808557, 
+        "rhomolar_min": 2981.053046244005
       }, 
       "gas_constant": 8.314471, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R116.json b/dev/fluids/R116.json
index d2c3489a..0ada8220 100644
--- a/dev/fluids/R116.json
+++ b/dev/fluids/R116.json
@@ -366,22 +366,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 293.03000000000003, 
-        "T_min": 293.02697325761744, 
+        "T_min": 293.02870328483243, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          5.973701413916427e-10, 
-          -8.378309573561642e-06, 
-          0.039073782995767505, 
-          232.42219731732985
+          1.5572847523698138e-09, 
+          -2.1246768945374408e-05, 
+          0.09657619729065436, 
+          146.77536264781335
         ], 
         "cV": [
-          -4.2587664193266785e-10, 
-          5.257573775768188e-06, 
-          -0.02149722855677295, 
-          322.1082759616395
+          -2.245407664058467e-09, 
+          2.9392570484872764e-05, 
+          -0.12820658247075012, 
+          479.3707443682296
         ], 
-        "rhomolar_max": 4535.77641861197, 
-        "rhomolar_min": 4355.023810307573
+        "rhomolar_max": 4501.228807035586, 
+        "rhomolar_min": 4388.313768041884
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R123.json b/dev/fluids/R123.json
index 508e8502..3f99128a 100644
--- a/dev/fluids/R123.json
+++ b/dev/fluids/R123.json
@@ -490,22 +490,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 456.831, 
-        "T_min": 456.7079808473738, 
+        "T_min": 456.8175322777658, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -5.2516982254248e-10, 
-          4.95822393582125e-06, 
-          -0.015285703141563677, 
-          472.1032632289936
+          7.413160414272145e-10, 
+          -8.948235265463442e-06, 
+          0.035598147140066136, 
+          410.0599459455676
         ], 
         "cV": [
-          5.019316578137991e-10, 
-          -6.104407328102757e-06, 
-          0.024431712288804266, 
-          424.57182248409964
+          -8.21928748519765e-10, 
+          7.918497516718821e-06, 
+          -0.0250634281364805, 
+          482.7835089382342
         ], 
-        "rhomolar_max": 3965.7364882421543, 
-        "rhomolar_min": 3221.873367889577
+        "rhomolar_max": 3721.7717264448725, 
+        "rhomolar_min": 3470.2289437901068
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R134a.json b/dev/fluids/R134a.json
index 4c27d0a8..37e93e88 100644
--- a/dev/fluids/R134a.json
+++ b/dev/fluids/R134a.json
@@ -400,22 +400,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 374.21, 
-        "T_min": 374.15599701305536, 
+        "T_min": 372.2699100419668, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -2.358891970526994e-10, 
-          3.35250579170572e-06, 
-          -0.015826824353177796, 
-          399.0175702243528
+          -3.17708038943435e-10, 
+          4.6452314558692645e-06, 
+          -0.022619828473249084, 
+          410.8918226766174
         ], 
         "cV": [
-          2.033032586375043e-10, 
-          -3.2541387283179285e-06, 
-          0.017300443262052236, 
-          343.6482870886872
+          0.0, 
+          -7.013970375511672e-07, 
+          0.007037892222874368, 
+          356.5552608547758
         ], 
-        "rhomolar_max": 5442.556273932187, 
-        "rhomolar_min": 4580.218882520725
+        "rhomolar_max": 6712.160594134622, 
+        "rhomolar_min": 3353.912381912076
       }, 
       "gas_constant": 8.314471, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R14.json b/dev/fluids/R14.json
index 95fc5056..6bc65901 100644
--- a/dev/fluids/R14.json
+++ b/dev/fluids/R14.json
@@ -435,22 +435,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 227.51, 
-        "T_min": 226.05575499770643, 
+        "T_min": 226.4221608783466, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -4.497162085380202e-11, 
-          7.584188775966138e-07, 
-          -0.003964719969167488, 
-          233.5234361790954
+          -3.276091146712226e-11, 
+          4.7283262023474423e-07, 
+          -0.0017555435908659005, 
+          227.86433767755432
         ], 
         "cV": [
-          5.850937467308107e-11, 
-          -1.409814381412894e-06, 
-          0.011174057273190223, 
-          198.30177311425936
+          4.0498841128300184e-11, 
+          -1.0634186146259112e-06, 
+          0.008979676508857887, 
+          202.86623067561814
         ], 
-        "rhomolar_max": 9311.871085841536, 
-        "rhomolar_min": 4879.2736322840055
+        "rhomolar_max": 9048.167089998266, 
+        "rhomolar_min": 5136.725032287401
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R143a.json b/dev/fluids/R143a.json
index e0211865..b731b52a 100644
--- a/dev/fluids/R143a.json
+++ b/dev/fluids/R143a.json
@@ -401,22 +401,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 345.857, 
-        "T_min": 345.85688760275673, 
+        "T_min": 345.85695155523047, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -5.242214594297355e-06, 
-          345.88388443543613
+          -3.3974084744314594e-06, 
+          345.8744234394907
         ], 
         "cV": [
           0.0, 
           0.0, 
-          5.221395136669298e-06, 
-          345.8302223361114
+          3.4270760473903566e-06, 
+          345.8394244118448
         ], 
-        "rhomolar_max": 5149.890794010884, 
-        "rhomolar_min": 5106.923714331294
+        "rhomolar_max": 5142.709330288575, 
+        "rhomolar_min": 5114.314110128164
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R22.json b/dev/fluids/R22.json
index 25fc7972..ab1ac2fe 100644
--- a/dev/fluids/R22.json
+++ b/dev/fluids/R22.json
@@ -493,22 +493,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 369.295, 
-        "T_min": 369.29299461397886, 
+        "T_min": 369.2949627574784, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -6.068711638786403e-11, 
-          9.60793099642547e-07, 
-          -0.004959370923967982, 
-          377.5706211619357
+          0.0, 
+          0.0, 
+          -2.3424000852304404e-06, 
+          369.3091907750444
         ], 
         "cV": [
-          2.0197560844726486e-11, 
-          -5.076049994717274e-07, 
-          0.003926491093801074, 
-          359.64667998370135
+          0.0, 
+          0.0, 
+          2.2501789373208953e-06, 
+          369.28136792095836
         ], 
-        "rhomolar_max": 6174.151068396738, 
-        "rhomolar_min": 5939.762656878844
+        "rhomolar_max": 6074.119299984461, 
+        "rhomolar_min": 6041.669084436526
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R236EA.json b/dev/fluids/R236EA.json
index 5a20d5f6..3f4cbd1e 100644
--- a/dev/fluids/R236EA.json
+++ b/dev/fluids/R236EA.json
@@ -414,22 +414,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 412.44, 
-        "T_min": 412.01703429466085, 
+        "T_min": 412.1479040101896, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -9.065638596766866e-10, 
-          9.956613016634915e-06, 
-          -0.036442262498707786, 
-          456.8904836061875
+          -8.006455677667769e-10, 
+          8.704410207568409e-06, 
+          -0.031523658993000074, 
+          450.4692091322586
         ], 
         "cV": [
-          8.719771420305249e-10, 
-          -9.978606681376363e-06, 
-          0.03803850767350116, 
-          364.13631933098907
+          7.013200127318413e-10, 
+          -8.186877070552625e-06, 
+          0.03179200998315829, 
+          371.36385032890547
         ], 
-        "rhomolar_max": 4440.255966785143, 
-        "rhomolar_min": 3017.4925122772956
+        "rhomolar_max": 4349.318832091479, 
+        "rhomolar_min": 3109.4495886851687
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R245fa.json b/dev/fluids/R245fa.json
index 6abd943d..03e63d46 100644
--- a/dev/fluids/R245fa.json
+++ b/dev/fluids/R245fa.json
@@ -407,22 +407,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 427.01, 
-        "T_min": 427.0096135546516, 
+        "T_min": 427.0098684058467, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
           0.0, 
-          -2.7068259197787627e-06, 
-          427.02048895043913
+          -1.216781979909817e-06, 
+          427.01471503017217
         ], 
         "cV": [
           0.0, 
           0.0, 
-          3.086102462886277e-06, 
-          426.9980413529563
+          1.440583268474931e-06, 
+          427.00441773983465
         ], 
-        "rhomolar_max": 4017.7669749909037, 
-        "rhomolar_min": 3749.7788341360238
+        "rhomolar_max": 3983.149327890093, 
+        "rhomolar_min": 3783.652171549889
       }, 
       "gas_constant": 8.3144621, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/R41.json b/dev/fluids/R41.json
index b9fe16e7..85f43370 100644
--- a/dev/fluids/R41.json
+++ b/dev/fluids/R41.json
@@ -377,22 +377,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 317.28000000000003, 
-        "T_min": 317.2695934234679, 
+        "T_min": 317.2733788557714, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          8.947784934150927e-11, 
-          -2.661886245206215e-06, 
-          0.0262942665921942, 
-          230.99772757769114
+          1.982286805306258e-10, 
+          -5.721729832650934e-06, 
+          0.05498977915002592, 
+          141.30084034516577
         ], 
         "cV": [
-          -8.480951160041928e-11, 
-          2.20398173327229e-06, 
-          -0.018988536263903795, 
-          371.46813146596344
+          -1.8833256878930853e-10, 
+          5.06762626683171e-06, 
+          -0.04539119693930791, 
+          452.60575575095083
         ], 
-        "rhomolar_max": 9571.518280811737, 
-        "rhomolar_min": 9026.378810480832
+        "rhomolar_max": 9510.503612422926, 
+        "rhomolar_min": 9087.67121079717
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/RC318.json b/dev/fluids/RC318.json
index a29c3d5e..f3fee459 100644
--- a/dev/fluids/RC318.json
+++ b/dev/fluids/RC318.json
@@ -433,22 +433,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 388.38, 
-        "T_min": 388.25698084737377, 
+        "T_min": 388.29054792405356, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          5.161678249152199e-10, 
-          -6.54174243254277e-06, 
-          0.0256755247809552, 
-          356.27486161409246
+          1.1298449787658047e-09, 
+          -1.2403349555998569e-05, 
+          0.04432498442528143, 
+          336.509525023081
         ], 
         "cV": [
-          -4.001990439211164e-10, 
-          1.9669817951712655e-06, 
-          -0.0006597242702549873, 
-          383.44477922926757
+          -1.04204053156705e-09, 
+          7.774300413950925e-06, 
+          -0.018161009518633232, 
+          401.01153126933485
         ], 
-        "rhomolar_max": 3376.736130176733, 
-        "rhomolar_min": 2825.886785898815
+        "rhomolar_max": 3333.3908947283726, 
+        "rhomolar_min": 2868.2068492030176
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Toluene.json b/dev/fluids/Toluene.json
index f76525e2..d7419a79 100644
--- a/dev/fluids/Toluene.json
+++ b/dev/fluids/Toluene.json
@@ -371,22 +371,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 591.75, 
-        "T_min": 591.7342932852254, 
+        "T_min": 591.743021298681, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          3.3834089871987155e-09, 
-          -3.464558495481263e-05, 
-          0.11764944401792847, 
-          459.1727413679192
+          1.2106006975063367e-08, 
+          -0.0001181388502205585, 
+          0.38403809215740176, 
+          175.87772723873658
         ], 
         "cV": [
-          -2.3379515587297088e-09, 
-          1.972502928601055e-05, 
-          -0.05458017218397031, 
-          641.0297738234855
+          -1.1414134593821325e-08, 
+          0.00010543398970811022, 
+          -0.32435919800801977, 
+          924.07044128592
         ], 
-        "rhomolar_max": 3253.6261257770193, 
-        "rhomolar_min": 3086.5243371577894
+        "rhomolar_max": 3222.9990473699186, 
+        "rhomolar_min": 3115.8882394651837
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/Xenon.json b/dev/fluids/Xenon.json
index 371ac6f9..2625f477 100644
--- a/dev/fluids/Xenon.json
+++ b/dev/fluids/Xenon.json
@@ -372,22 +372,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 289.733, 
-        "T_min": 289.72843171770734, 
+        "T_min": 289.73036241968293, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          2.4311831644858725e-10, 
-          -6.354625581839551e-06, 
-          0.05529442454906748, 
-          129.54501621008842
+          6.004785820072694e-10, 
+          -1.540656966562575e-05, 
+          0.13172106414321377, 
+          -85.54244066647958
         ], 
         "cV": [
-          -2.2130895526715094e-10, 
-          5.34493631486394e-06, 
-          -0.04294825043876369, 
-          404.53030033147684
+          -6.058430701055764e-10, 
+          1.4986162139205343e-05, 
+          -0.12352266285870138, 
+          628.9853784946181
         ], 
-        "rhomolar_max": 8554.90344650679, 
-        "rhomolar_min": 8248.286253998665
+        "rhomolar_max": 8512.969220623036, 
+        "rhomolar_min": 8288.926931935599
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Butane.json b/dev/fluids/n-Butane.json
index 452ed5b7..2508cccc 100644
--- a/dev/fluids/n-Butane.json
+++ b/dev/fluids/n-Butane.json
@@ -471,22 +471,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 425.125, 
-        "T_min": 425.1219732576174, 
+        "T_min": 425.12491360192047, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -1.6020493306008252e-10, 
-          1.133822562422527e-06, 
-          -0.0014996904947787396, 
-          423.23116044183894
+          0.0, 
+          0.0, 
+          -5.692661766826853e-06, 
+          425.1473310005959
         ], 
         "cV": [
-          5.058796197557434e-11, 
-          -1.3472509771444817e-06, 
-          0.008234549282093268, 
-          410.50072741365295
+          0.0, 
+          0.0, 
+          8.526909313167263e-06, 
+          425.0915508992536
         ], 
-        "rhomolar_max": 3985.810039412961, 
-        "rhomolar_min": 3859.458487995192
+        "rhomolar_max": 3937.946709931644, 
+        "rhomolar_min": 3912.637210218117
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Decane.json b/dev/fluids/n-Decane.json
index 8214e197..cc40a0ef 100644
--- a/dev/fluids/n-Decane.json
+++ b/dev/fluids/n-Decane.json
@@ -371,22 +371,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 617.7, 
-        "T_min": 617.6842932852254, 
+        "T_min": 617.6916108089977, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          3.811704985816065e-08, 
-          -0.00019945721156220926, 
-          0.3466608020285197, 
-          417.5042285213912
+          1.0320134681362064e-07, 
+          -0.0005217594566020225, 
+          0.8786599904848911, 
+          124.80648856211926
         ], 
         "cV": [
-          -3.8653700756418197e-08, 
-          0.00017824366286806788, 
-          -0.2727502335438755, 
-          756.1055367913187
+          -1.1142857846667393e-07, 
+          0.0005339799193483449, 
+          -0.8523592215306723, 
+          1070.881951847099
         ], 
-        "rhomolar_max": 1678.7818428517664, 
-        "rhomolar_min": 1601.198950562281
+        "rhomolar_max": 1667.390392847361, 
+        "rhomolar_min": 1612.6301589021477
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Dodecane.json b/dev/fluids/n-Dodecane.json
index 4610986b..4a92bfce 100644
--- a/dev/fluids/n-Dodecane.json
+++ b/dev/fluids/n-Dodecane.json
@@ -380,22 +380,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 658.1, 
-        "T_min": 658.0986713196614, 
+        "T_min": 658.0987032848325, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
           0.0, 
-          -2.1192739463715689e-07, 
-          0.0005637268697348361, 
-          657.7251216316264
+          -2.0939062487280465e-07, 
+          0.0005569790621618195, 
+          657.7296089236623
         ], 
         "cV": [
-          1.345410821444352e-08, 
-          -5.389362597299564e-05, 
-          0.07196012902658075, 
-          626.0728305909759
+          1.3346771828287604e-08, 
+          -5.346984610199855e-05, 
+          0.07140247657014234, 
+          626.3174076977489
         ], 
-        "rhomolar_max": 1409.180220111776, 
-        "rhomolar_min": 1288.4723365719328
+        "rhomolar_max": 1408.694372900752, 
+        "rhomolar_min": 1288.843365778471
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Hexane.json b/dev/fluids/n-Hexane.json
index 9cdf5639..a11ec61b 100644
--- a/dev/fluids/n-Hexane.json
+++ b/dev/fluids/n-Hexane.json
@@ -388,22 +388,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 507.82, 
-        "T_min": 506.8564813947396, 
+        "T_min": 507.56389285976036, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          8.758829336463305e-09, 
-          -8.028744783668493e-05, 
-          0.24210552253394685, 
-          267.0302268919283
+          1.3977737160597438e-07, 
+          -0.0011682233690808838, 
+          3.251884108736999, 
+          -2507.157926239475
         ], 
         "cV": [
-          3.991905207393978e-09, 
-          -3.342318035828356e-05, 
-          0.09319459234659805, 
-          421.2768792846532
+          5.874354703279542e-09, 
+          -4.7886457822250056e-05, 
+          0.130117701932496, 
+          389.9695505583025
         ], 
-        "rhomolar_max": 3123.268752501498, 
-        "rhomolar_min": 2157.714974917123
+        "rhomolar_max": 2833.509856115492, 
+        "rhomolar_min": 2364.9453716716366
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Nonane.json b/dev/fluids/n-Nonane.json
index 5551e00f..fbc8f53f 100644
--- a/dev/fluids/n-Nonane.json
+++ b/dev/fluids/n-Nonane.json
@@ -370,22 +370,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 594.5500000000001, 
-        "T_min": 594.5262937515283, 
+        "T_min": 594.5305381064545, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          2.6268572567217745e-08, 
-          -0.00015162277736042532, 
-          0.2906990422823534, 
-          409.3502826161235
+          3.439621959142905e-08, 
+          -0.00019618497909856946, 
+          0.3721332593263793, 
+          359.74973708777674
         ], 
         "cV": [
-          -2.3832710380126962e-08, 
-          0.00012016817674452382, 
-          -0.2007737723861744, 
-          705.5893640684056
+          -3.3806685877357655e-08, 
+          0.00017381238995556715, 
+          -0.2969386008307187, 
+          763.0469880912561
         ], 
-        "rhomolar_max": 1866.189822592916, 
-        "rhomolar_min": 1755.3631417347385
+        "rhomolar_max": 1860.332444076972, 
+        "rhomolar_min": 1760.985320673019
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Pentane.json b/dev/fluids/n-Pentane.json
index 26280299..ad162a5f 100644
--- a/dev/fluids/n-Pentane.json
+++ b/dev/fluids/n-Pentane.json
@@ -406,22 +406,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 469.70000000000005, 
-        "T_min": 469.06161506402384, 
+        "T_min": 469.36685791273345, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -1.5350222378894414e-09, 
-          1.4495090265584156e-05, 
-          -0.04560406484397615, 
-          517.5028217560338
+          -1.1076982598336214e-09, 
+          1.0116271697455407e-05, 
+          -0.03069871503131287, 
+          500.6421885129799
         ], 
         "cV": [
-          1.3419945158856869e-09, 
-          -1.3857242599790237e-05, 
-          0.047489652270097, 
-          415.6565744315043
+          4.3055773822385574e-10, 
+          -5.541145426556296e-06, 
+          0.022280143554586573, 
+          441.03601546584997
         ], 
-        "rhomolar_max": 3899.8810879232615, 
-        "rhomolar_min": 2607.6316735875685
+        "rhomolar_max": 3750.9260751689894, 
+        "rhomolar_min": 2757.127555479338
       }, 
       "gas_constant": 8.31451, 
       "gas_constant_units": "J/mol/K", 
diff --git a/dev/fluids/n-Propane.json b/dev/fluids/n-Propane.json
index a0e46fde..1ab024f6 100644
--- a/dev/fluids/n-Propane.json
+++ b/dev/fluids/n-Propane.json
@@ -452,22 +452,22 @@
       ], 
       "critical_region_splines": {
         "T_max": 369.89, 
-        "T_min": 369.88310506132734, 
+        "T_min": 369.8896425409525, 
         "_note": "Coefficients for the critical cubic spline.  T = c[0]*rho^3 + c[1]*rho^2 + c[2]*rho + c[3] with rho in mol/m^3 and T in K", 
         "cL": [
-          -1.2699463565482216e-10, 
-          1.6385267569449435e-06, 
-          -0.0068606698953377855, 
-          379.1045100099181
+          0.0, 
+          0.0, 
+          -9.567201907483823e-06, 
+          369.9378360095374
         ], 
         "cV": [
-          1.3753113621718563e-10, 
-          -2.32949579930026e-06, 
-          0.012980122776713688, 
-          346.03538907178984
+          0.0, 
+          0.0, 
+          9.857730275302854e-06, 
+          369.8407113486235
         ], 
-        "rhomolar_max": 5155.238965206609, 
-        "rhomolar_min": 4845.222396586998
+        "rhomolar_max": 5037.36296682965, 
+        "rhomolar_min": 4963.738199610669
       }, 
       "gas_constant": 8.314472, 
       "gas_constant_units": "J/mol/K",