I made a pw.xcalculation for the compound FeRh to estimate the value of a, the problem is thatI always find a value that doubles the expected value Do you have any idea what to do thank you -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20120920/7c4b6916/attachment.htm