Hello.

The best free thermodynamic library is CoolProp and the best paid library remains NISTRefprop.

From my limited use of both i can state that:

1. NIST Refprop has a larger library of substances

2. NIST Refprop library of organics and mixtures is more extensive

3. CoolProp is free for unlimited use while NIST Refprop is limited by license

4. You cannot include NIST Refprop library in public code

5. CoolProp has better integration with most of the popular programming languages and MS office products

6. You can call NIST Refprop data (from your installation) from CoolProp

7. Accuracy of predicted values from both libraries are same

So if your substance is present in CoolProp, use it.

Best regards.

Thank you Dr Aliyu Abdulhammeed Bello ...

useful information

I want to add that the best licensed library is definitely "Dortmund Database".

You can check online if the desired data set is available and you can purchase it without paying the entire data base.

If you have access to literature, the Dechema data series might help you also with your problem.

Best regards

Thomas