III.G.7. (XIII.B.3.) (XIII.D.5.) |
Compare vibrational frequencies for two calculations for Na2S (Sodium sulfide)
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 | Σg | Σg | 258 | 268 | -10.2 | 0.962 | 22.990 | 22.990 | 0.000 | 1.000 | 0.00 | 0.00 | 0.00 | ||||
2 | Σu | Σu | 391 | 406 | -15.2 | 0.963 | 27.556 | 27.556 | 0.000 | 1.000 | 150.93 | 130.85 | 20.08 | 1.153 | |||
3 | Πu | Πu | 5i | 51i | 45.6 | 0.101 | 27.556 | 27.556 | 0.000 | 1.000 | 88.18 | 61.83 | 26.35 | 1.426 | |||
4 | Πu | Πu | 5i | 51i | 45.6 | 0.101 | 27.556 | 27.556 | 0.000 | 1.000 | 88.18 | 61.83 | 26.35 | 1.426 | |||
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.