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 CCSD(T)=FULL/aug-cc-pVTZ
Calculated values were scaled by 0.9637.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CHONH2 formamide 12 torsion A" 289 90 -199 3.205
CH2CCH2 allene 1 A1 3015 1051 -1964 2.869
CH2CCH2 allene 8 E 3086 1440 -1646 2.144
HCNO fulminic acid 5 torsion Π 224 -84 -308 -2.684
H2CS- thioformaldehyde anion 4 B1 450 317 -133 1.421
SiF2+ Silicon difluoride cation 2 A1 350 274 -76 1.276
CH3 Methyl radical 2 torsion A2" 606 470 -137 1.292
CH2OH Hydroxymethyl radical 9 torsion A 234 405 171 0.577
HCCN cyanomethylene 5 Π 129 -332 -461 -0.388
CHCl2 dichloromethyl radical 4 A' 190 292 102 0.651
CH2Cl chloromethyl radical 4 B1 402 74 -328 5.400
BF3+ boron trifluoride cation 5 B2 1791 663 -1128 2.700
NO2 Nitrogen dioxide 1 A1 1318 1988 670 0.663
NO2 Nitrogen dioxide 2 A1 750 -165 -915 -4.544
NO2 Nitrogen dioxide 3 B2 1618 2050 432 0.789
BCl3+ Boron Trichloride cation 3 E' 1104 632 -472 1.748
AsSe Arsenic monoselenide 1 Σ 280 402 122 0.696
C3 carbon trimer 3 Πu 63 102 38 0.623
S3 Sulfur trimer 2 A1 281 566 285 0.497
SiH2D2 silane-d2 6 B1 2183 1574 -609 1.387
SiH2D2 silane-d2 8 B2 1601 2178 577 0.735
NH4 Ammonium radical 1 A1 2552 2965 413 0.861
Cl3- trichloride anion 2 Σu 327 250 -77 1.310
BH3PH3 borane phosphine 12 E 447 347 -100 1.290
H2OH2O water dimer 8 A' 103 148 45 0.697
H2OH2O water dimer 12 A" 88 131 43 0.671
H2POH Phosphinous acid 9 A" 375 263 -113 1.429
CHFCl Chlorofluoromethyl radical 6 A 540 395 -145 1.367
H2CNCN cyanamide, methylene 3 A' 2208 2993 785 0.738
H2CNCN cyanamide, methylene 4 A' 1621 2190 569 0.740
HCNH+ N-protonated HCN 1 Σ 3483 -7800 -11283 -0.446
HCNH+ N-protonated HCN 2 Σ 3188 -18412 -21600 -0.173
HCNH+ N-protonated HCN 3 Σ 2156 -29286 -31442 -0.074
HCNH+ N-protonated HCN 4 Π 802 -23541 -24343 -0.034
HCNH+ N-protonated HCN 5 Π 646 -18711 -19357 -0.035
ONNO NO dimer 3 A1 135 247 112 0.545
ONNO NO dimer 4 torsion A2 117 209 92 0.560
AlNC Aluminum isocyanide 3 Π 100 165 65 0.604