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Compare vibrational frequencies for two calculations for SNO (Nitrogen oxide 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)   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'   1668 1674 -6.8 0.996   14.803 14.789 0.014 1.001   488.99 319.62 169.37 1.530   312.23 88.81 223.42 3.516
2 A' A'   729 879 -150.4 0.829   18.451 18.214 0.237 1.013   22.06 12.18 9.88 1.811   11.76 26.08 -14.32 0.451
3 A' A'   419 521 -102.5 0.803   16.175 16.398 -0.224 0.986   5.48 1.98 3.50 2.767   22.42 143.42 -121.00 0.156
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.