9 [verified] — Nist Refprop

| Feature | REFPROP 9 (Legacy) | REFPROP 10 / 10.0 (Current) | | :--- | :--- | :--- | | | ~147 | 200+ (including carbon capture solvents and new low-GWP refrigerants) | | Mixture Model | GERG-2008 (excellent for natural gas) | GERG-2012 (improved for CO2-rich mixtures) | | Transport Properties | Stable, mature correlations | Novel models for ionic liquids and nanorefrigerants | | User Interface | Classic, simple Windows GUI | Modernized with live plotting and tabular exports | | Programming | 32-bit and 64-bit DLL | 64-bit only; Python wrappers improved | | License Cost | No longer for sale (legacy users only) | Active sales; academic discounts available |

: Supports calculations across liquid, gas, and supercritical phases, as well as subcooled and metastable regions. Fluid Support nist refprop 9