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Compare vibrational frequencies for two calculations for H2COO (Dioxymethyl radical)


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)   Raman Activity (Å4/u)
mode number A B   A B diff. ratio   A B diff. ratio   A B diff. ratio   A B diff. ratio
1 A' A'   3085 3207 -122.1 0.962   1.127 1.132 -0.005 0.995   3.01 1.01 2.00 2.973          
2 A' A'   2970 3041 -71.2 0.977   1.055 1.041 0.014 1.013   13.92 13.23 0.70 1.053          
3 A' A'   1740 1412 327.2 1.232   6.967 1.258 5.709 5.538   111.46 0.99 110.47 112.502          
4 A' A'   1440 1238 202.3 1.163   1.118 2.257 -1.139 0.495   18.35 40.90 -22.55 0.449          
5 A' A'   1221 1129 91.3 1.081   1.408 3.539 -2.131 0.398   17.92 280.22 -262.30 0.064          
6 A' A'   471 1040 -569.2 0.453   11.188 3.991 7.196 2.803   35.33 572.58 -537.25 0.062          
7 A' A'   408 528 -120.0 0.773   3.443 2.959 0.484 1.163   12.33 7.15 5.17 1.724          
8 A" A"   1174 739 435.1 1.589   1.347 1.460 -0.113 0.923   4.99 30.30 -25.30 0.165          
9 A" A"   572 624 -51.7 0.917   1.186 1.171 0.015 1.013   0.19 42.70 -42.51 0.004          
scaled by     0.8985 0.943
19 08 20 15 07

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.