I have the exercise to get activity coefficients of some components with Cosmotherm. This was not really difficult. But I checked out the boiling points which Cosmotherm calculated for atmosphere pressure. These boiling points were all completely wrong. That is why I also checked out forr water. The values for density, boiling point and critial propertys were all wrong. Why Cosmotherm cannot calculate the easiest component. Water is in the database, so why I get there also completely wrong values. I do not know someone who can help me much with Cosmotherm, but I got the advice that I have to tune the Cosmo-RS parameters. But we do not know how to handle it for water neither for the components I have to calculate. Sorry for my english, I am from Germany :-)