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 MP4=FULL/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 0.670
HCN+ hydrogen cyanide cation 1 Σ 3050 3577 527 0.853
HCN+ hydrogen cyanide cation 2 Σ 1800 2783 983 0.647
CH2I2 Diiodomethane 3 A1 704 504 -200 1.398
CH2I2 Diiodomethane 4 A1 285 119 -166 2.401
CH2I2 Diiodomethane 7 B1 896 722 -174 1.241
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 193 -2767 15.319
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 252 -2708 11.746
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 674 -772 2.146
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 766 -678 1.884
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1483 757 0.490
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1493 863 0.422
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3103 2852 0.081
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3113 2911 0.065
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 115 -2895 26.096
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 758 -2252 3.970
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 980 -279 1.285
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3163 2400 0.241
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3188 3065 0.039
CHSNH2 thioformamide 12 A" 393 253 -140 1.551
F2CCCF2 tetrafluoroallene 5 B2 2052 729 -1323 2.816
F2CCCF2 tetrafluoroallene 6 B2 1030 582 -448 1.768
F2CCCF2 tetrafluoroallene 7 B2 581 391 -190 1.484
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 700 -2379 4.400
CO+ carbon monoxide cation 1 Σ 2184 2738 554 0.798
H2CS- thioformaldehyde anion 4 B1 450 251 -199 1.792
CaO Calcium monoxide 1 Σ 723 1934 1212 0.374
CFCl2 dichlorofluoromethyl radical 2 A' 747 618 -129 1.210
CH2NH+ Methanimine cation 4 A' 1370 1861 491 0.736
CN Cyano radical 1 Σ 2042 2726 684 0.749
CH2Cl chloromethyl radical 4 B1 402 172 -230 2.331
HNC+ hydrogen isocyanide cation 2 Σ 2195 2698 503 0.814
HN3+ Hydrazoic acid cation 2 A' 1850 3004 1154 0.616
IF5 pentafluoroiodine 2 A1 616 312 -304 1.975
NO Nitric oxide 1 Σ 1876 3362 1486 0.558
NaO2 Sodium superoxide 3 B2 333 792 460 0.420
C3 carbon trimer 3 Πu 63 207 143 0.307
S3 Sulfur trimer 2 A1 281 574 293 0.489
NI3 Nitrogen triiodide 3 E 354 510 156 0.694
SiH3Cl chlorosilane 5 E 954 2306 1352 0.414
XeF4 Xenon tetrafluoride 5 B2u 216 161 -55 1.345
SiH2D2 silane-d2 6 B1 2183 1651 -532 1.323
SiH2D2 silane-d2 8 B2 1601 2284 683 0.701
OPCl Phosphorus oxychloride 2 A' 308 499 191 0.618
OPCl Phosphorus oxychloride 3 A' 492 301 -191 1.636
CHFCl Chlorofluoromethyl radical 6 A 540 410 -130 1.316
H2CNCN cyanamide, methylene 3 A' 2208 3087 879 0.715
H2CNCN cyanamide, methylene 4 A' 1621 2144 523 0.756
SNO Nitrogen oxide sulfide 3 A' 792 513 -279 1.543
INO Nitrosyl iodide 2 A' 216 471 255 0.458
INO Nitrosyl iodide 3 A' 470 220 -250 2.133