III.G.7. (XIII.B.3.) (XIII.D.5.) |
Compare vibrational frequencies for two calculations for CO2+ (Carbon dioxide cation)
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 | 1218 | 1310 | -91.6 | 0.930 | 15.995 | 15.995 | 0.000 | 1.000 | 0.00 | 0.00 | 0.00 | ||||
2 | Σu | Σu | 865 | 1579i | 2443.3 | -0.548 | 12.877 | 12.877 | 0.000 | 1.000 | 229.49 | 1784.33 | -1554.83 | 0.129 | |||
3 | Πu | Πu | 550 | 549 | 0.8 | 1.001 | 12.877 | 12.877 | 0.000 | 1.000 | 59.12 | 61.56 | -2.44 | 0.960 | |||
4 | Πu | Πu | 383 | 547 | -163.5 | 0.701 | 12.877 | 12.877 | 0.000 | 1.000 | 41.87 | 32.69 | 9.18 | 1.281 | |||
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.