PC GAMESS/Firefly-related discussion club

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Jaden Curtis
jaden_curtis@yahoo.com

I am a long time Gaussian user who is new to PC GAMESS.  As such, I have been performing a few basic calculations in order to familiarize myself with the program.  I have run into a problem while trying to optimize the geometry of a simple molecule in an excited state.  Specifically, I cannot determine the how to tell the program to optimize the geometry while the molecule is in the excited state.  All of my efforts thus far simply yield the ground state energy and geometry.  For simplicity, I have been using CIS to generate the excited states.  My feeling is that there is some simple nuance I am missing that needs to be placed in the input file.  I should also mention I am aware of the information that is punched into the .dat file of the program pertaining to certain properties of the excited state.  However, I’m not sure if it is necessary to read this information back into a new input file to relax the excited state geometry.  Thanks for the help.