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: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

Bad vibrational frequency predictions

19 02 11 15 45

Calculated frequencies that differ from experiment by more than 400 cm-1 or have a ratio with experiment outside of 0.7 to 1.2 are listed

Calculated vibrational frequencies ("theory" in table) are calculated at CISD/6-311+G(3df,2p)
Calculated values were scaled by 0.9218.

Species Name mode int rot Symmetry Experiment Theory difference ratio
HCN+ hydrogen cyanide cation 2 Σ 1800 2272 472 0.792
CH3CH2CH2CH3 Butane 5 Ag 1442 407 -1035 3.544
CH3CH2CH2CH3 Butane 8 Ag 1151 813 -338 1.415
CH3CH2CH2CH3 Butane 36 Bu 271 2955 2684 0.092
C3O2 Carbon suboxide 7 Πu 61 -67 -128 -0.911
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 677 -2402 4.550
C6H6 Benzvalene 10 A1 996 753 -243 1.323
H2CS- thioformaldehyde anion 4 B1 450 278 -172 1.617
CH2Cl chloromethyl radical 4 B1 402 -73 -475 -5.510
HN3+ Hydrazoic acid cation 2 A' 1850 2427 577 0.762
NF3 Nitrogen trifluoride 1 A1 1032 682 -350 1.513
NF3 Nitrogen trifluoride 2 A1 647 1094 447 0.592
NF3 Nitrogen trifluoride 3 E 907 520 -387 1.744
NF3 Nitrogen trifluoride 4 E 492 1032 540 0.477
CaBr2 Calcium dibromide 3 Πu 72 38 -34 1.904
N2O4 Dinitrogen tetroxide 3 Ag 265 390 125 0.679
AsSe Arsenic monoselenide 1 Σ 280 404 124 0.692
SiC2 Silicon dicarbide 3 B2 196 -80 -276 -2.461
S3 Sulfur trimer 2 A1 281 606 325 0.464
SiH2D2 silane-d2 6 B1 2183 1518 -665 1.438
SiH2D2 silane-d2 8 B2 1601 2100 499 0.762
Br3- tribromide anion 2 Σu 214 133 -81 1.606
B5H9 pentaborane9 13 B1 240 584 344 0.411
B5H9 pentaborane9 16 B2 1036 782 -254 1.325
B5H9 pentaborane9 18 B2 600 457 -143 1.312
B5H9 pentaborane9 22 E 1409 1045 -364 1.349
OPCl Phosphorus oxychloride 2 A' 308 486 178 0.633
OPCl Phosphorus oxychloride 3 A' 492 305 -187 1.614
CHFCl Chlorofluoromethyl radical 6 A 540 395 -145 1.366
H2CNCN cyanamide, methylene 3 A' 2208 2947 739 0.749
H2CNCN cyanamide, methylene 4 A' 1621 2253 632 0.720
SNO Nitrogen oxide sulfide 1 A' 1527 485 -1042 3.151
ONNO NO dimer 1 A1 1868 418 -1450 4.470
ONNO NO dimer 2 A1 239 359 120 0.667
ONNO NO dimer 5 B2 1789 811 -978 2.205