Subject: G98: How to calculate excited singlet states with ROHF ?

From: Johannes Weber <[email-masked]>
Date: 11 Jun 2001 19:31:41 +0200

Dear CCL members,

I have a Gaussian 98 related question:

(How) is it possible to do calculations on excited singlet states
different from the ground state symmetry with the restricted open
shell method ?

There is no problem with this for triplet states since there must be
at least two unpaired electrons in different MOs and one can change
these MOs by guess=alter.  Alas, for the singlets the program always
seems to follow the aufbau principle resulting in a closed shell
system. Is anybody aware of a workaround?

Thanks in advance, :-)ohannes.

PS: On demand I will summarize the answers.
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| Johannes Weber                     | Email:                        |
| Universitaet zu Koeln              | [email-masked]   |
| Institut fuer Physikalische Chemie | tel: 0049-(0)221-470-4816     |
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