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IV.C.1. (XIII.D.1.)

Compare vibrational frequencies in CCCBDB for CH3CCCH3 (2-Butyne)

mPW1PW91/3-21G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1' 2924 8 A1' 2916  
2 A1' 2301 61 A1' 2240  
3 A1' 1408 28 A1' 1380  
4 A1' 692 -33 A1' 725  
5 A2" 2924        
6 A2" 1402 -1536 A2" 2938  
7 A2" 1118 -264 A2" 1382  
8 E' 2987 1835 A2" 1152  
9 E' 1482 -1491 E' 2973  
10 E' 1063 -393 E' 1456  
11 E' 198 -856 E' 1054  
12 E" 2988 2775 E' 213  
13 E" 1482 -1484 E" 2966  
14 E" 1045 -403 E" 1448  
15 E" 414 -615 E" 1029  
16   -371 E" 371  
The calculated vibrational frequencies were scaled by 0.9546

See section XIII.C.3 List or set vibrational scaling factors to change the scale factors used here.
See section III.B.3.c Calculate a vibrational scaling factor for a set of molecules to determine the least squares best scaling factor.
See section III.B.3.b List of vibrational scaling factors and their uncertainties for information on where the above scaling factor is from.