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/aug-cc-pVDZ
Calculated values were scaled by 0.9687.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 300 100 0.666
C2H6O2S Dimethyl sulfone 20 B1 262 193 -69 1.358
C2H2 Acetylene 4 Πg 612 420 -192 1.457
HCN+ hydrogen cyanide cation 3 Π 760 1264 504 0.601
CHONH2 formamide 12 torsion A" 289 49 -240 5.917
CH3SCH3+ dimethyl sulfide cation 15 B1 172 138 -34 1.246
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 551 -144 1.261
CH3CH2CH2CH3 Butane 5 Ag 1442 412 -1030 3.500
CH3CH2CH2CH3 Butane 8 Ag 1151 823 -328 1.399
CH3CH2CH2CH3 Butane 36 Bu 271 3010 2739 0.090
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 190 -2770 15.556
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 243 -2717 12.171
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 636 -810 2.272
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 729 -715 1.980
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1429 703 0.508
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1436 806 0.439
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3016 2765 0.083
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3025 2823 0.067
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 106 -2904 28.373
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 739 -2271 4.076
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 952 -307 1.323
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3078 2315 0.248
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3100 2977 0.040
C3H6O 2-Propen-1-ol 24 A 188 107 -82 1.765
CHSNH2 thioformamide 12 A" 393 290 -103 1.353
C3F6 hexafluoropropene 21 A" 60 40 -20 1.519
C4H2 Diacetylene 7 Πg 482 -593 -1075 -0.812
C4H2 Diacetylene 9 Πu 231 150 -81 1.544
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1001 -390 1.389
C3H6O Oxetane 18 B1 90 -64 -154 -1.399
C3O2 Carbon suboxide 7 Πu 61 -126 -187 -0.485
HCNO fulminic acid 5 torsion Π 224 125 -99 1.792
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 660 -2419 4.664
P(CH3)3 trimethylphosphine 22 E 259 196 -63 1.319
C6H6 Benzvalene 10 A1 996 741 -255 1.343
H2CS- thioformaldehyde anion 4 B1 450 223 -227 2.018
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 254 -83 1.327
SiF2+ Silicon difluoride cation 2 A1 350 276 -74 1.267
C2H Ethynyl radical 3 torsion Π 372 235 -136 1.578
CH3 Methyl radical 2 torsion A2" 606 481 -126 1.262
CH2OH Hydroxymethyl radical 9 torsion A 234 413 179 0.566
HCCN cyanomethylene 5 Π 129 -484 -613 -0.266
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.648
CH2Cl chloromethyl radical 4 B1 402 -164 -566 -2.444
HClO4 perchloric acid 12 A" 191 135 -56 1.413
BF3+ boron trifluoride cation 5 B2 1791 401 -1389 4.462
OClO- Chlorine dioxide anion 2 A1 418 319 -99 1.310
BCl3+ Boron Trichloride cation 3 E' 1104 687 -417 1.607
C3O Tricarbon monoxide 5 Π 109 -86 -195 -1.262
SiC2 Silicon dicarbide 3 B2 196 -179 -375 -1.099
C3 carbon trimer 3 Πu 63 -185 -248 -0.343
TiO Titanium monoxide 1 Σ 1000 11448 10448 0.087
C4 Carbon tetramer 4 Πg 323 -171 -494 -1.886
C4 Carbon tetramer 5 Πu 160 128 -32 1.249
SiHF3 trifluorosilane 6 E 306 802 496 0.381
SiH2D2 silane-d2 6 B1 2183 1567 -616 1.393
SiH2D2 silane-d2 8 B2 1601 2169 568 0.738
N(SiH3)3 trisilylamine 4 A' 974 2151 1177 0.453
N(SiH3)3 trisilylamine 6 A' 493 929 436 0.531
N(SiH3)3 trisilylamine 9 A" 748 2155 1407 0.347
NH4 Ammonium radical 1 A1 2552 2956 404 0.863
GeF Germanium monofluoride 1 Σ 809 624 -186 1.298
BrO+ Bromine monoxide cation 1 Σ 840 621 -219 1.353
Cl3- trichloride anion 2 Σu 327 213 -114 1.532
B5H9 pentaborane9 13 B1 240 591 351 0.406
B5H9 pentaborane9 16 B2 1036 773 -263 1.340
B5H9 pentaborane9 18 B2 600 459 -141 1.308
B5H9 pentaborane9 22 E 1409 1051 -358 1.341
OPCl Phosphorus oxychloride 2 A' 308 467 159 0.660
OPCl Phosphorus oxychloride 3 A' 492 285 -207 1.728
H2OH2O water dimer 12 A" 88 126 38 0.699
F3- trifluoride anion 2 Σu 550 311 -239 1.771
H2POH Phosphinous acid 9 A" 375 245 -130 1.530
Mg2 Magnesium diatomic 1 Σg 48 19 -29 2.546
CHFCl Chlorofluoromethyl radical 6 A 540 391 -149 1.381
H2CNCN cyanamide, methylene 3 A' 2208 3007 799 0.734
H2CNCN cyanamide, methylene 4 A' 1621 2202 581 0.736
SNO Nitrogen oxide sulfide 3 A' 792 490 -303 1.618
ONNO NO dimer 2 A1 239 373 134 0.641
ONNO NO dimer 3 A1 135 313 178 0.430
ONNO NO dimer 4 torsion A2 117 213 96 0.550
ONNO NO dimer 6 B2 429 699 270 0.614
AlNC Aluminum isocyanide 3 Π 100 78 -22 1.277