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)/TZVP
Calculated values were scaled by 0.9632.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 318 118 0.629
C2H4 Ethylene 7 B2g 940 722 -217 1.301
C2H2 Acetylene 4 Πg 612 92 -520 6.627
HCN+ hydrogen cyanide cation 3 Π 760 1587 827 0.479
CH3CCH propyne 9 E 633 479 -154 1.321
CH3CCH propyne 10 E 328 -101 -429 -3.236
CHONH2 formamide 12 torsion A" 289 -348 -636 -0.831
CH3SCH3 Dimethyl sulfide 11 torsion A2 175 116 -59 1.505
C2Br4 tetrabromoethene 4 Au 66 52 -14 1.277
C6H4Cl2 1,2-dichlorobenzene 12 A2 975 696 -279 1.402
C6H4Cl2 1,2-dichlorobenzene 13 A2 850 645 -205 1.317
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 135 -560 5.159
C6H4Cl2 1,2-dichlorobenzene 15 A2 504 -184 -688 -2.746
C6H4Cl2 1,2-dichlorobenzene 16 A2 152 -1530 -1682 -0.099
C6H4Cl2 1,2-dichlorobenzene 17 B1 940 656 -284 1.434
C6H4Cl2 1,2-dichlorobenzene 19 B1 435 210 -225 2.067
C6H4Cl2 1,2-dichlorobenzene 20 B1 239 -167 -406 -1.428
CH3CH2CH2CH3 Butane 5 Ag 1442 410 -1032 3.517
CH3CH2CH2CH3 Butane 8 Ag 1151 821 -330 1.401
CH3CH2CH2CH3 Butane 36 Bu 271 2999 2728 0.090
CHCCH2CH3 1-Butyne 24 torsion A" 213 165 -48 1.289
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 189 -2771 15.668
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 240 -2720 12.345
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 626 -820 2.309
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 731 -713 1.976
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1442 716 0.503
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1447 817 0.435
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3008 2757 0.083
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3018 2816 0.067
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 113 -2897 26.589
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 752 -2258 4.003
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 957 -302 1.316
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3069 2306 0.249
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3093 2970 0.040
C3H6O 2-Propen-1-ol 24 A 188 115 -73 1.632
C4H5N Pyrrole 10 A2 864 646 -218 1.337
C4H5N Pyrrole 11 A2 692 524 -168 1.321
C4H5N Pyrrole 12 A2 614 -357 -971 -1.722
C4H5N Pyrrole 16 B1 475 -118 -592 -4.027
CHSNH2 thioformamide 12 A" 393 -235 -628 -1.669
C3F6 hexafluoropropene 21 A" 60 32 -28 1.871
CH2CClCHCH2 1,3-Butadiene, 2-chloro- 20 A" 926 709 -217 1.306
CH2CClCHCH2 1,3-Butadiene, 2-chloro- 24 A" 144 61 -83 2.353
C4H4Se selenophene 9 A2 915 662 -253 1.383
C4H4Se selenophene 11 A2 535 240 -295 2.225
C3H4N2 1H-Imidazole 21 A" 539 177 -362 3.041
CH2N4 1H-Tetrazole 15 A" 578 406 -172 1.424
CH3CHFCH3 2-Fluoropropane 27 A" 243 193 -50 1.259
C4H2 Diacetylene 7 Πg 482 166 -316 2.908
C4H2 Diacetylene 9 Πu 231 155 -76 1.493
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1002 -389 1.388
F2CCCF2 tetrafluoroallene 5 B2 2052 701 -1351 2.926
F2CCCF2 tetrafluoroallene 6 B2 1030 562 -468 1.833
F2CCCF2 tetrafluoroallene 7 B2 581 379 -202 1.534
F2CCCF2 tetrafluoroallene 11 E 90 69 -21 1.299
CH2CCH2 allene 1 A1 3015 1042 -1973 2.894
CH2CCH2 allene 8 E 3086 1446 -1640 2.134
CH2CO Ketene 6 B1 528 416 -112 1.270
C3H6O Oxetane 18 B1 90 -76 -166 -1.179
C3O2 Carbon suboxide 7 Πu 61 -166 -227 -0.367
HCNO fulminic acid 5 torsion Π 224 -265 -489 -0.845
C6H4F2 1,4-difluorobenzene 7 Au 945 655 -290 1.442
C6H4F2 1,4-difluorobenzene 8 Au 420 185 -235 2.274
C6H4F2 1,4-difluorobenzene 15 B2g 928 702 -226 1.321
C6H4F2 1,4-difluorobenzene 16 B2g 692 346 -346 2.000
C6H4F2 1,4-difluorobenzene 18 B2g 374 -1055 -1429 -0.355
CH3OC2H5 Ethane, methoxy- 30 A" 115 87 -28 1.318
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 644 -2435 4.783
HCCBr bromoacetylene 5 Π 295 185 -110 1.594
HCCCl Chloroacetylene 4 Π 604 475 -129 1.272
HCCCl Chloroacetylene 5 Π 326 113 -213 2.876
P(CH3)3 trimethylphosphine 22 E 259 170 -89 1.523
C6H6 Benzvalene 10 A1 996 744 -252 1.339
CH3PHCH3 dimethylphosphine 24 A" 184 120 -64 1.531
H2CS- thioformaldehyde anion 4 B1 450 -65 -515 -6.917
CH2CHSH Ethenethiol 13 A" 972 707 -265 1.375
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 166 -171 2.025
CH2ClCCCl 1,3-dichloropropyne 15 A" 176 67 -109 2.613
C4H4 cyclobutadiene 11 B2g 531 367 -164 1.448
CaO Calcium monoxide 1 Σ 723 486 -236 1.486
SiF2+ Silicon difluoride cation 2 A1 350 269 -81 1.300
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.669
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 269 -187 1.697
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 75 -96 2.284
C3H5 Allyl radical 11 B1 802 577 -225 1.389
C2H- Ethynyl anion 3 Π 505 335 -170 1.507
CH3 Methyl radical 2 torsion A2" 606 450 -156 1.346
CNN Diazocarbene 3 Π 396 279 -117 1.419
CH2OH Hydroxymethyl radical 8 torsion A 482 690 208 0.699
CH2OH Hydroxymethyl radical 9 torsion A 234 433 199 0.540
HCCN cyanomethylene 5 Π 129 -548 -676 -0.235
C6H6 Trimethylenecycopropane 9 A2" 885 642 -243 1.379
C6H6 Trimethylenecycopropane 10 A2" 212 71 -141 2.969
C6H6 Trimethylenecycopropane 20 E" 340 -113 -453 -3.022
CHCl2 dichloromethyl radical 4 A' 190 294 104 0.647
CH2Cl chloromethyl radical 4 B1 402 -181 -583 -2.226
HCP+ Phosphaethyne cation 3 Π 718 561 -156 1.278
BF3+ boron trifluoride cation 5 B2 1791 889 -902 2.014
MgF2 Magnesium fluoride 3 Πu 165 128 -37 1.287
NF3 Nitrogen trifluoride 1 A1 1032 616 -416 1.676
NF3 Nitrogen trifluoride 2 A1 647 987 340 0.656
NF3 Nitrogen trifluoride 3 E 907 469 -438 1.935
NF3 Nitrogen trifluoride 4 E 492 875 383 0.562
CaBr2 Calcium dibromide 3 Πu 72 47 -25 1.516
OClO- Chlorine dioxide anion 2 A1 418 304 -114 1.376
BCl3+ Boron Trichloride cation 3 E' 1104 609 -495 1.814
N2O4 Dinitrogen tetroxide 4 torsion Au 82 64 -18 1.272
SF5 Sulfur pentafluoride 2 A1 633 503 -130 1.258
SF5 Sulfur pentafluoride 7 E 818 576 -242 1.421
C3O Tricarbon monoxide 5 Π 109 -127 -236 -0.860
Li2O dilithium oxide 3 Πu 112 60 -52 1.864
SiC2 Silicon dicarbide 3 B2 196 -129 -326 -1.519
C3 carbon trimer 3 Πu 63 -195 -258 -0.325
C4 Carbon tetramer 4 Πg 323 -233 -556 -1.383
S3 Sulfur trimer 2 A1 281 529 248 0.531
KrF2 Krypton difluoride 1 Σg 449 343 -106 1.308
SiH2D2 silane-d2 6 B1 2183 1582 -601 1.380
SiH2D2 silane-d2 8 B2 1601 2189 588 0.731
BH2NH2 Boranamine 8 B1 670 509 -161 1.316
GeF Germanium monofluoride 1 Σ 809 625 -184 1.295
HBNH Boranimine 5 Π 461 351 -110 1.314
C5H6N+ Pyridinium 19 B1 667 348 -319 1.917
B4H10 Tetraborane(10) 11 A1 785 548 -237 1.432
B4H10 Tetraborane(10) 12 A1 559 226 -333 2.468
B4H10 Tetraborane(10) 19 A2 662 401 -261 1.651
B4H10 Tetraborane(10) 36 B2 236 344 108 0.686
Cl3- trichloride anion 2 Σu 327 252 -75 1.295
B5H9 pentaborane9 13 B1 240 595 355 0.403
B5H9 pentaborane9 16 B2 1036 782 -254 1.324
B5H9 pentaborane9 18 B2 600 463 -137 1.295
B5H9 pentaborane9 22 E 1409 1072 -337 1.315
CaS Calcium sulfide 1 Σ 459 321 -138 1.429
OPCl Phosphorus oxychloride 2 A' 308 474 166 0.650
OPCl Phosphorus oxychloride 3 A' 492 289 -203 1.704
H2OH2O water dimer 8 A' 103 164 61 0.629
F3- trifluoride anion 1 Σg 461 368 -93 1.252
H2POH Phosphinous acid 9 A" 375 257 -118 1.459
Mg2 Magnesium diatomic 1 Σg 48 11 -37 4.376
CHFCl Chlorofluoromethyl radical 6 A 540 392 -148 1.377
H2CNCN cyanamide, methylene 3 A' 2208 2990 782 0.739
H2CNCN cyanamide, methylene 4 A' 1621 2165 544 0.749
C2H3NO Nitrosoethylene 11 A' 490 337 -153 1.454
SNO Nitrogen oxide sulfide 1 A' 1527 489 -1038 3.124
ONNO NO dimer 3 A1 135 90 -44 1.494
AlNC Aluminum isocyanide 3 Π 100 65 -35 1.548