III.G.7. (XIII.B.3.) (XIII.D.5.) |
Compare vibrational frequencies for two calculations for CH3 (Methyl radical)
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' | 2951 | 3036 | -84.5 | 0.972 | 1.008 | 1.008 | 0.000 | 1.000 | 0.00 | 0.00 | 0.00 | ||||
2 | A2" | A2" | 277 | 380 | -103.2 | 0.728 | 1.236 | 83.24 | 93.99 | -10.76 | 0.886 | ||||||
3 | E' | E' | 3110 | 3214 | -103.7 | 0.968 | 1.119 | 1.119 | 0.000 | 1.000 | 11.66 | 4.23 | 7.43 | 2.755 | |||
4 | E' | E' | 3110 | 3214 | -103.7 | 0.968 | 1.119 | 11.66 | 4.23 | 7.43 | 2.755 | ||||||
5 | E' | E' | 1384 | 1396 | -12.8 | 0.991 | 1.102 | 1.102 | -0.000 | 1.000 | 0.55 | 2.35 | -1.80 | 0.235 | |||
6 | E' | E' | 1384 | 1396 | -12.8 | 0.991 | 1.102 | 0.55 | 2.35 | -1.80 | 0.235 | ||||||
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.