III.G.7. (XIII.B.3.) (XIII.D.5.) |
Compare vibrational frequencies for two calculations for H2S- (Hydrogen sulfide anion)
A =
HF/6-31G*
B =
MP2/6-31G*
scale factors=0.8985, 0.943
symmetry | frequency (cm-1) | reduced mass (amu) | IR Intensity (km mol-1) | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
mode number | A | B | A | B | diff. | ratio | A | B | diff. | ratio | A | B | diff. | ratio | |||
1 | A1 | A1 | 1496 | 1640 | -143.7 | 0.912 | 1.025 | 1.033 | -0.008 | 0.992 | 254.01 | 292.64 | -38.63 | 0.868 | |||
2 | A1 | A1 | 1247 | 1304 | -56.5 | 0.957 | 1.051 | 1.042 | 0.009 | 1.008 | 132.92 | 89.64 | 43.28 | 1.483 | |||
3 | B2 | B2 | 4553i | 4966i | 412.6 | 0.917 | 1.033 | 1.033 | -0.000 | 1.000 | 16817.19 | 25333.39 | -8516.20 | 0.664 | |||
scaled by | 0.8985 | 0.943 |
See section III.C.1 List or set vibrational scaling factors
to change the scale factors used here.
See section III.C.2
Calculate a vibrational scaling factor for a given set of molecules
to determine the least squares best scaling factor.