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 HNO+ (Nitrosyl hydride cation)


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

scale factors=0.8985, 0.943 -11.358 8.978
  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'   2833 5001 -2167.9 0.566   1.075 12.433 0.086   275.34 15141.39 0.018
2 A' A'   1830 2796 -966.0 0.654   10.041 1.063 9.446   34.70 396.09 0.088
3 A' A'   952 644 307.7 1.477   1.254 1.266 -0.012 0.990   343.31 736.16 0.466
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.