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 C6H10 (Cyclopentene, 4-methyl-)


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

scale factors=0.8985, 0.943 0.301
  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   3046 3074 -27.9 0.991   1.105 1.104 0.001 1.001   36.64 24.61 1.489
2 A A   3021 3051 -30.0 0.990   1.086 1.086 0.001 1.001   13.15 5.46 2.409
3 A A   2926 3001 -75.2 0.975   1.102 1.103 -0.001 0.999   95.18 21.40 4.447
4 A A   2924 3001 -77.2 0.974   1.103 1.103 0.000 1.000   45.09 34.52 1.306
5 A A   2904 2961 -57.0 0.981   1.095 1.098 -0.003 0.997   41.82 31.57 1.325
6 A A   2898 2958 -60.3 0.980   1.095 1.098 -0.003 0.997   48.79 23.61 2.067
7 A A   2871 2919 -48.5 0.983   1.082 1.077 0.005 1.005   6.86 22.16 0.310
8 A A   2870 2917 -46.7 0.984   1.040 1.042 -0.002 0.998   58.46 17.87 3.271
9 A A   2854 2894 -40.0 0.986   1.070 1.066 0.004 1.004   37.15 33.58 1.106
10 A A   2854 2893 -39.0 0.987   1.070 1.068 0.003 1.003   43.31 18.81 2.302
11 A A   1663 1593 69.5 1.044   6.001 5.700 1.053   2.42 1.51 1.602
12 A A   1483 1475 7.5 1.005   1.096 1.055 0.041 1.039   2.66 7.86 0.338
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.