III.G.7. (XIII.B.3.) (XIII.D.5.) |
Compare vibrational frequencies for two calculations for HCNH (methyleneazane)
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 | A' | A' | 3219 | 3248 | -28.5 | 0.991 | 1.075 | 1.100 | -0.026 | 0.977 | 2.51 | 18.07 | -15.57 | 0.139 | |||
2 | A' | A' | 2919 | 2885 | 34.2 | 1.012 | 1.088 | 1.261 | -0.173 | 0.863 | 33.03 | 323.74 | -290.71 | 0.102 | |||
3 | A' | A' | 1497 | 2339 | -841.4 | 0.640 | 6.433 | 3.742 | 2.691 | 1.719 | 0.67 | 390.15 | -389.47 | 0.002 | |||
4 | A' | A' | 1137 | 985 | 151.9 | 1.154 | 1.474 | 1.256 | 0.219 | 1.174 | 116.70 | 89.89 | 26.81 | 1.298 | |||
5 | A' | A' | 910 | 699 | 210.3 | 1.301 | 1.045 | 1.172 | -0.126 | 0.892 | 45.48 | 332.42 | -286.94 | 0.137 | |||
6 | A" | A" | 955 | 896 | 59.9 | 1.067 | 1.285 | 1.335 | -0.050 | 0.962 | 8.56 | 12.02 | -3.45 | 0.713 | |||
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.