return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Vibrations > Vibrations > 2 calculations

Compare vibrational frequencies for two calculations for C5H10O (Oxetane, 3,3-dimethyl-)


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'   2936 3009 -73.0 0.976     1.103     97.59 18.88 5.169
2 A' A'   2934 3004 -69.8 0.977     1.103     76.46 24.30 3.146
3 A' A'   2925 2967 -42.0 0.986     1.109     31.40 55.12 0.570
4 A' A'   2893 2918 -24.3 0.992     1.036     8.33 15.93 0.523
5 A' A'   2873 2914 -41.5 0.986     1.035     33.77 19.64 1.720
6 A' A'   2868 2899 -31.1 0.989     1.061     26.81 31.70 0.846
7 A' A'   1524 1502 22.9 1.015     1.117     0.94 1.29 0.734
8 A' A'   1481 1476 4.5 1.003     1.062     3.68 4.47 0.823
9 A' A'   1468 1463 4.9 1.003     1.054     2.72 3.78 0.719
10 A' A'   1415 1389 26.0 1.019     1.244     3.05 3.37 0.905
11 A' A'   1401 1373 27.3 1.020     1.354     3.87 10.04 0.386
12 A' A'   1386 1336 49.3 1.037     1.821     5.31 0.27 19.721
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.