return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Vibrations > Vibrations

Compare vibrational frequencies in CCCBDB for C2H4O4 (Formic acid dimer)

B3LYP/3-21G*

18 11 26 13 55
Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency Scaled
Frequency
Harm.
diff
Fund.
diff
Symmetry Harmonic
Frequency
Fundamental
Frequency
Comment
1 Ag 3120 3001           
2 Ag 2219 2134   -815 Ag   2949 C-H was 2
3 Ag 1630 1568   -102 Ag   1670 C=O was 3
4 Ag 1475 1419   4 Ag   1415 C-O-H was 4
5 Ag 1392 1339   -36 Ag   1375 H-C-O was 5
6 Ag 1276 1227   13 Ag   1214 C-O was 6
7 Ag 688 662   -15 Ag   677 O-C=O was 7
8 Ag 293 282           
9 Ag 192 185   48 Ag   137 ipb O-H.O was 9
10 Au 1235 1188   138 Au   1050 opb C-H was 13
11 Au 1057 1017   95 Au   922 opb O-H was 14
12 Au 220 212   44 Au   168 opb O-H.O was 15
13 Au 97 94   24 Au   69 twist was 16
14 Bg 1184 1139   79 Bg   1060 opb C-H was 10
15 Bg 1073 1032           
16 Bg 315 303   73 Bg   230 opb O-H.O was 12
17 Bu 3118 3000   -84 Bu   3084 O-H was 17
18 Bu 2485 2391   -548 Bu   2939 C-H was 18
19 Bu 1691 1627   -119 Bu   1746 C=O was 19
20 Bu 1511 1454   -0 Bu   1454 C-O-H was 20
21 Bu 1438 1383   19 Bu   1364 H-C-O was 21
22 Bu 1269 1221   3 Bu   1218 C-O was 22
23 Bu 742 713   15 Bu   698 O-C=O was 23
24 Bu 423 407   139 Bu   268 O-H.O was 24
The calculated vibrational frequencies were scaled by 0.962

See section Calculated; Vibrations; Scale Factors; Set scaling factors to change the scale factors used here.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to determine the least squares best scaling factor.
See section Calculated; Vibrations; Scale Factors; Scale factor uncertainty for information on where the above scaling factor is from.