III.G.7. (XIII.B.3.) (XIII.D.5.) |
Compare vibrational frequencies for two calculations for NNS (Nitrogen 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 | Σ | Σ | 2337 | 1706 | 630.7 | 1.370 | 14.003 | 14.067 | -0.064 | 0.995 | 297.04 | 467.56 | -170.51 | 0.635 | |||
2 | Σ | Σ | 526 | 796 | -270.1 | 0.661 | 18.985 | 18.869 | 0.116 | 1.006 | 44.93 | 28.19 | 16.74 | 1.594 | |||
3 | Π | Π | 422 | 431 | -9.6 | 0.978 | 14.392 | 14.468 | -0.076 | 0.995 | 1.66 | 0.00 | 1.65 | 338.551 | |||
4 | Π | Π | 422 | 431 | -9.6 | 0.978 | 14.392 | 14.468 | -0.076 | 0.995 | 1.66 | 0.00 | 1.65 | 338.551 | |||
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.