Subject: C-H stretch IR Int.

From: [email-masked]
Date: 11 Jul 1997 12:22:58 +0200

I use quantumchemical programs to simulate IR spectra (for instance:
G94 HF/6-31G**) with Komorinickis and McIvers method to calculate
dipole moment derivative tensors. I use the conventional harmonic
approximation to calculate normal modes to determine the IR
Intensities.

Why are the IR--intensities of the C-H stretch modes calculated this
way too low in comparison with experiments? Is that due to
anharmonicities, if so -- how do anharmonicities influence the IR
intensities? Are there references dealing with this topic?

Replies can send to me directly, I will summarize to the list.
Please use
   [email-masked]
for direct replies.

thank you very much in advance
Rupert Rebentisch

-- 
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| Rupert Rebentisch                  | [email-masked]     |
| Institut fuer Physikalische Chemie | fax: 0049-(0)221-470-5144     |
| Lehrstuhl Prof. Dr. G. Hohlneicher | tel: 0049-(0)221-470-4816     |
| Universitaet zu Koeln              | www.rrz.uni-koeln.de/~acp50   |  
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