return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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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 ROHF/3-21G*
Calculated values were scaled by 0.9085.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 torsion Au 84 336 251 0.251
CH2ClCHO chloroacetaldehyde 15 torsion A 27 66 39 0.408
C2H2O2 Ethanedial 7 torsion Au 127 192 65 0.663
H2CS- thioformaldehyde anion 4 B1 450 -198 -648 -2.273
C2H Ethynyl radical 3 torsion Π 372 733 362 0.507
CH3 Methyl radical 2 torsion A2" 606 170 -436 3.558
CH2OH Hydroxymethyl radical 8 torsion A 482 786 304 0.614
CH2OH Hydroxymethyl radical 9 torsion A 234 360 126 0.650
HCCN cyanomethylene 2 Σ 1735 2212 477 0.784
HCCN cyanomethylene 5 Π 129 -775 -904 -0.166
C2H3+ vinyl cation 2 A1 2217 2899 682 0.765
CHCl2 dichloromethyl radical 4 A' 190 294 104 0.647
CH2Cl chloromethyl radical 4 B1 402 -372 -774 -1.082
HN3 hydrogen azide 4 A' 1151 838 -313 1.373
HN3+ Hydrazoic acid cation 2 A' 1850 2388 538 0.775
HN3+ Hydrazoic acid cation 4 A' 850 456 -394 1.866
NF3 Nitrogen trifluoride 1 A1 1032 570 -462 1.809
NF3 Nitrogen trifluoride 2 A1 647 986 339 0.656
NF3 Nitrogen trifluoride 3 E 907 439 -468 2.066
NF3 Nitrogen trifluoride 4 E 492 1031 539 0.477
OClO- Chlorine dioxide anion 1 A1 790 296 -494 2.665
OClO- Chlorine dioxide anion 2 A1 418 239 -179 1.746
OClO- Chlorine dioxide anion 3 B2 823 536 -287 1.537
AsSe Arsenic monoselenide 1 Σ 280 420 140 0.666
MgOH magnesium hydroxide 3 torsion Π 188 358 170 0.525
C4 Carbon tetramer 4 Πg 323 501 178 0.644
NBr nitrogen monobromide 1 Σ 682 94 -589 7.293
PO Phosphorus monoxide 1 Σ 1220 718 -503 1.700
BrO+ Bromine monoxide cation 1 Σ 840 386 -454 2.176
ClOO chloroperoxy radical 1 A' 1443 991 -452 1.455
ClOO chloroperoxy radical 2 A' 414 714 300 0.580
ClOO chloroperoxy radical 3 A' 201 391 190 0.515
CHFCl Chlorofluoromethyl radical 6 A 540 371 -169 1.455
HNB hydrogen nitrogen boron 3 Π 433 626 193 0.691
ZnCH3 Zinc monomethyl 6 E 315 595 280 0.530
ClSO Sulfur chloride oxide 1 A' 1163 733 -430 1.586
SNO Nitrogen oxide sulfide 1 A' 1527 418 -1109 3.650
BrOO Bromine dioxide 1 A' 1487 995 -492 1.495
NSO sulfinyl amidogen 3 A' 300 451 151 0.666