Posted by Evgeny K. Dolgov on April 15, 2004 at 09:32:20:
My colleagues and I considered to purchase Molcas for calculations of vibronic spectra (gas phase) of relatively small (10-20 atoms)organic molecules. The most beneficial feature of Molcas 5 (when comparing with other programs) was the CASPT2 analytic gradients for excited states. Now I'm told that "This work is as yet unfinished" (c) Molcas manual. And now Molcas has only numeric derivatives like other programs. So, a lot of questions arises. (1) Is it still possible to by a version of Molcas with analytic CASPT2 gradients (considering that we don't need QM/MM, DFT, relativistic corrections and other stuff like this)? (2) (the main question) was the analytic gradient code of Molcas as good as we think or maybe we really shouldn't by this program? (3) May be the analytic gradient code will be available within Molcas 6 later? But why this was not mentioned in the "Coming features" section of the manual?