Subject: vibrational modes of symmetric linear anion

From: XIAOFENG FRANK DUAN <[email-masked]>
Date: Thu, 16 Aug 2001 11:30:21 -0400

Dear CCLers:

One of my colleaque raised following problem:
For a five-atom centrosymmetric linear molecule (D.infinte.h symmetry)
in its neutral form (closed shell), 4 Sigma and 3 Pi vibrational modes
could be obtained with G98 with no difficulties. For the -1 anion of the
molecule ( has the same symmetry, but open shell),  supposedly it should
have same vibrational modes. However, with G98 (also Jaguar) the
symmetries of some vibrational  modes cannot be determined, and there
are no degenerate frequencies for Pi modes. With GAMESS, if the D4h
symmetry  is used, the symmetries of the modes can be determined
correctly but it results in a few imaginary frequencies.
We'd like to hear opions and solutions about the problem from your!

Thanks!

Frank

--
 Xiaofeng Frank Duan, Ph.D         |  Phone: 937-904-8307
 ASC MSRC                          |  Email: [email-masked]
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