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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 MP3=FULL/aug-cc-pVTZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 288 88 0.695
C2H2+ acetylene cation 4 Πg 572 834 262 0.685
HCN+ hydrogen cyanide cation 1 Σ 3050 3500 450 0.871
HCN+ hydrogen cyanide cation 2 Σ 1800 2715 915 0.663
C3O2 Carbon suboxide 7 Πu 61 45 -16 1.361
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 729 -2350 4.226
CO+ carbon monoxide cation 1 Σ 2184 2736 552 0.798
LiOH lithium hydroxide 1 Σ 3688 4131 443 0.893
LiOH lithium hydroxide 3 Π 257 372 115 0.690
CH2NH+ Methanimine cation 4 A' 1370 1878 508 0.729
CN Cyano radical 1 Σ 2042 2733 691 0.747
C2H Ethynyl radical 2 Σ 1841 2455 614 0.750
C2H Ethynyl radical 3 torsion Π 372 784 413 0.474
HOCO Hydrocarboxyl radical 1 A' 3316 3778 462 0.878
CHCl2 dichloromethyl radical 4 A' 190 308 118 0.616
CH2Cl chloromethyl radical 4 B1 402 59 -343 6.832
HNC+ hydrogen isocyanide cation 2 Σ 2195 2731 536 0.804
HN3+ Hydrazoic acid cation 2 A' 1850 2889 1039 0.640
O3 Ozone 3 B2 1042 1700 657 0.613
NO Nitric oxide 1 Σ 1876 2507 631 0.748
AsSe Arsenic monoselenide 1 Σ 280 450 170 0.622
NS Mononitrogen monosulfide 1 Σ 1204 1639 435 0.735
C3 carbon trimer 3 Πu 63 121 58 0.524
S3 Sulfur trimer 2 A1 281 621 340 0.452
SiH2D2 silane-d2 6 B1 2183 1651 -532 1.322
SiH2D2 silane-d2 8 B2 1601 2285 684 0.701
NH4 Ammonium radical 1 A1 2552 3142 590 0.812
BH3PH3 borane phosphine 12 E 447 366 -81 1.221
OPCl Phosphorus oxychloride 2 A' 308 520 212 0.593
OPCl Phosphorus oxychloride 3 A' 492 320 -172 1.539
H2OH2O water dimer 8 A' 103 151 48 0.683
H2OH2O water dimer 12 A" 88 132 44 0.668
CHFCl Chlorofluoromethyl radical 6 A 540 419 -121 1.288
H2CNCN cyanamide, methylene 3 A' 2208 3148 940 0.701
H2CNCN cyanamide, methylene 4 A' 1621 2424 803 0.669
SNO Nitrogen oxide sulfide 1 A' 1527 1269 -258 1.203
SNO Nitrogen oxide sulfide 3 A' 792 -2974 -3767 -0.266
ONNO NO dimer 3 A1 135 312 178 0.431
ONNO NO dimer 4 torsion A2 117 241 124 0.486
ONNO NO dimer 6 B2 429 721 292 0.595