DFT frequency scaling factor <SUMMARY>
I'd like to thank those who replied to my question
regarding DFT frequency scaling factors.
-Dongchul Lim, lim.,at,.rani.chem.yale.edu
>Are there scaling factors for frequencies from different
>DFT methods, especially BECKE3LYP?
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The scaling factor for BECKE3LYP seems pretty close to one, 0.989
according to one study, see:
C. W. Bauschlicher and H. Partridge, J. Chem. Phys. 98 (1994) 11623.
I think that even for non-empirical functionals (LDA, Perdew's GGA)
scaling factors would not help much (they would probably turn out
close to one).
|-------------------------------|-----------------------------|
| Rene Fournier | fournier.,at,.physics.unlv.edu |
| Department of Physics | fournie.,at,.ned1.sims.nrc.ca |
| University of Nevada | phone : (702) 895 1706 |
| Las Vegas, NV 89154-4002 USA | FAX : (702) 895 0804 |
|-------------------------------|-----------------------------|
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For the B-LYP method, the scaling factor is close to one. However, a scale
factor of 0.9613 is required for the Becke3LYP method for reliable prediction
of fundamental frequencies. The 0.9613 value was derived from comparison with
experimental frequencies of a large set of molecules (1066 frequencies for 122
molecules).
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|| __ |\ Dr. Ming Wah (Richard) Wong ||
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