Henry, > I have since discovered that this site: http://openmopac.net/ > is up, and contains chapter and verse on MOPAC 7.1/2 (as the new > code appears to be called). There is a link for source code for 7.1, > and executable for 7.2 This is fantastic news! I mentioned the RM1 paper because I was somewhat surprised to see Jimmy's name attached to a reparameterization. (Yes, I know there are lots of "new" semiempirical reparameterizations all the time.) I think it's great that MOPAC is open again -- I know there have been a lot of people hoping to get PM5 and transition metals, and this is really going to help. The website seems to indicate that he's primarily targeting Windows .exe, but I suspect we can help him port to other platforms and spin some packages. Cheers, -Geoff -- -Dr. Geoffrey Hutchison <grh25 at cornell.edu> Cornell University, Department of Chemistry and Chemical Biology Abruña Group http://abruna.chem.cornell.edu/