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 QCISD(T)/Def2TZVPP
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 299 99 0.669
C2H6O2S Dimethyl sulfone 20 B1 262 212 -50 1.239
HCN+ hydrogen cyanide cation 3 Π 760 2470 1710 0.308
CH2I2 Diiodomethane 3 A1 704 500 -204 1.407
CH2I2 Diiodomethane 4 A1 285 118 -167 2.405
CH2I2 Diiodomethane 7 B1 896 726 -170 1.234
CH2I2 Diiodomethane 9 B2 738 610 -128 1.211
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 194 -2766 15.275
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 251 -2709 11.804
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 665 -781 2.173
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 761 -683 1.899
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1486 760 0.489
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1494 864 0.422
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3107 2856 0.081
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3119 2917 0.065
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 112 -2898 26.760
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 760 -2250 3.960
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 978 -281 1.287
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3166 2403 0.241
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3192 3069 0.039
F2CCCF2 tetrafluoroallene 5 B2 2052 734 -1318 2.794
F2CCCF2 tetrafluoroallene 6 B2 1030 585 -445 1.761
F2CCCF2 tetrafluoroallene 7 B2 581 394 -187 1.476
CH2CCH2 allene 1 A1 3015 1082 -1933 2.787
CH2CCH2 allene 8 E 3086 1490 -1596 2.071
C3O2 Carbon suboxide 7 Πu 61 -18 -79 -3.335
CBr4 Carbon tetrabromide 3 T2 672 275 -397 2.440
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 690 -2389 4.465
H2CS- thioformaldehyde anion 4 B1 450 193 -257 2.326
CaO Calcium monoxide 1 Σ 723 1799 1076 0.402
CFCl2 dichlorofluoromethyl radical 2 A' 747 616 -131 1.212
CH2Cl chloromethyl radical 4 B1 402 137 -265 2.935
TeO2 Tellurium Dioxide 1 A1 823 279 -544 2.947
NF3 Nitrogen trifluoride 1 A1 1032 654 -378 1.578
NF3 Nitrogen trifluoride 2 A1 647 1045 398 0.619
NF3 Nitrogen trifluoride 3 E 907 498 -409 1.820
NF3 Nitrogen trifluoride 4 E 492 930 438 0.529
CaBr2 Calcium dibromide 3 Πu 72 40 -32 1.785
BCl3+ Boron Trichloride cation 3 E' 1104 596 -508 1.853
N2O4 Dinitrogen tetroxide 4 torsion Au 82 64 -18 1.276
SiC2 Silicon dicarbide 3 B2 196 162 -34 1.213
C4 Carbon tetramer 5 Πu 160 100 -60 1.594
S3 Sulfur trimer 2 A1 281 579 298 0.485
NI3 Nitrogen triiodide 3 E 354 545 191 0.650
XeF4 Xenon tetrafluoride 5 B2u 216 171 -45 1.263
SiH2D2 silane-d2 6 B1 2183 1636 -547 1.334
SiH2D2 silane-d2 8 B2 1601 2263 662 0.708
GeF Germanium monofluoride 1 Σ 809 674 -135 1.200
CHFCl Chlorofluoromethyl radical 6 A 540 410 -130 1.319
H2CNCN cyanamide, methylene 3 A' 2208 3091 883 0.714
H2CNCN cyanamide, methylene 4 A' 1621 2241 620 0.723
C2H3NO Nitrosoethylene 11 A' 490 343 -147 1.427
SNO Nitrogen oxide sulfide 1 A' 1527 503 -1024 3.037
ONNO NO dimer 3 A1 135 228 93 0.591
ONNO NO dimer 4 torsion A2 117 207 90 0.566
INO Nitrosyl iodide 2 A' 216 493 277 0.438
INO Nitrosyl iodide 3 A' 470 229 -241 2.052