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Compare vibrational frequencies for two calculations for Be(OH)2 (Beryllium hydroxide)


A = HF/6-31G*
B = MP2/6-31G*

scale factors=0.8985, 0.943 1.508 -0.328 0.734 -6.895 7.110 -6.383 1.519
  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 A1   3786 3712 73.8 1.020   1.068 1.068 0.000 1.000   39.39 57.36 0.687
2 A A1   689 698 -9.8 0.986   6.557 5.049 1.299   4.04 10.49 0.385
3 A A1   512 550 -38.6 0.930   1.574 1.902 0.827   131.94 185.03 0.713
4 A A1   288 262 25.7 1.098   2.984 2.250 1.326   76.21 4.77 15.982
5 A A2   184 230i 414.5 -0.800   1.079 1.128 -0.049 0.957   155.46 0.00  
6 B B1   3784 320 3463.2 11.806   1.068 7.963 0.134   193.07 69.55 2.776
7 B B2   1430 3710 -2279.5 0.386   8.179 1.068 7.655   438.23 164.78 2.660
8 B B2   512 1456 -944.4 0.351   1.577 7.961 0.198   455.98 340.32 1.340
9 B B2   273 416 -143.3 0.656   2.676 1.157 2.313   125.99 357.10 0.353
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.