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

Compare vibrational frequencies in CCCBDB for C5H8 (1,2-Butadiene, 3-methyl-)

MP2/6-31+G**

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3034 47 A1 2987  
2 A1 3022 81 A1 2941  
3 A1 2918 2 A1 2916  
4 A1 1935 -61 A1 1996  
5 A1 1462 -8 A1 1470  
6 A1 1424 -14 A1 1438  
7 A1 1366 -3 A1 1369  
8 A1 1259 -27 A1 1286  
9 A1 986 13 A1 973  
10 A1 704 -22 A1 726  
11 A1 323 -26 A1 349  
12 A2 2991 50 A2 2941  
13 A2 1425 -45 A2 1470  
14 A2 963 -22 A2 985  
15 A2 590 -27 A2 617  
16 A2 138        
17 B1 3107 56 B1 3051  
18 B1 2990 49 B1 2941  
19 B1 1438 -32 B1 1470  
20 B1 1045 -23 B1 1068  
21 B1 976 -28 B1 1004  
22 B1 362 -81 B1 443  
23 B1 225 38 B1 187  
24 B1 145        
25 B2 3033 92 B2 2941  
26 B2 2916 0 B2 2916  
27 B2 1440 -30 B2 1470  
28 B2 1351 -18 B2 1369  
29 B2 1181 -10 B2 1191  
30 B2 936 -32 B2 968  
31 B2 822 -26 B2 848  
32 B2 559 5 B2 554  
33 B2 167 -20 B2 187  
The calculated vibrational frequencies were scaled by 0.9406

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.