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)=FULL/6-31+G**
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 319 119 0.627
HCN+ hydrogen cyanide cation 3 Π 760 2035 1275 0.373
CH3CCH propyne 10 E 328 249 -79 1.315
CH3SCH3+ dimethyl sulfide cation 15 B1 172 137 -35 1.251
C2Br4 tetrabromoethene 7 B2g 464 991 527 0.468
CH2BrCH2Br Ethane, 1,2-dibromo- 10 A 91 73 -18 1.252
CH3CH2CH2CH3 Butane 5 Ag 1442 431 -1011 3.347
CH3CH2CH2CH3 Butane 8 Ag 1151 861 -290 1.337
CH3CH2CH2CH3 Butane 36 Bu 271 3160 2889 0.086
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 193 -2767 15.338
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 254 -2706 11.662
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 661 -785 2.187
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 772 -672 1.871
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1525 799 0.476
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1528 898 0.412
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3155 2904 0.080
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3165 2963 0.064
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 140 -2870 21.499
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 785 -2225 3.836
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 1013 -246 1.242
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3220 2457 0.237
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3245 3122 0.038
C4H5N Pyrrole 16 B1 475 389 -85 1.219
CHSNH2 thioformamide 12 A" 393 210 -183 1.874
CH2CClCHCH2 1,3-Butadiene, 2-chloro- 24 A" 144 109 -35 1.318
C3H4N2 1H-Imidazole 21 A" 539 436 -103 1.236
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1038 -353 1.340
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1287 397 0.691
F2CCCF2 tetrafluoroallene 5 B2 2052 716 -1336 2.867
F2CCCF2 tetrafluoroallene 6 B2 1030 561 -469 1.837
F2CCCF2 tetrafluoroallene 7 B2 581 382 -199 1.520
CH2CCH2 allene 1 A1 3015 1086 -1929 2.775
CH2CCH2 allene 8 E 3086 1520 -1566 2.030
C3H6O Oxetane 18 B1 90 -100 -190 -0.899
C3O2 Carbon suboxide 7 Πu 61 158 97 0.386
HCNO fulminic acid 5 torsion Π 224 -238 -462 -0.940
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 698 -2381 4.413
HCCBr bromoacetylene 5 Π 295 449 154 0.657
HCCCl Chloroacetylene 5 Π 326 212 -114 1.535
P(CH3)3 trimethylphosphine 22 E 259 196 -63 1.322
C6H6 Benzvalene 10 A1 996 780 -216 1.277
H2CS- thioformaldehyde anion 4 B1 450 250 -200 1.799
CH2ClCCCl 1,3-dichloropropyne 9 A' 282 226 -56 1.245
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 170 -167 1.979
GeO2 Germanium dioxide 3 Πu 196 153 -42 1.275
LiOH lithium hydroxide 3 Π 257 547 290 0.469
SiF2+ Silicon difluoride cation 2 A1 350 290 -60 1.207
CH3 Methyl radical 2 torsion A2" 606 488 -119 1.243
CH2 Methylene 1 A1 2806 3207 401 0.875
CH2OH Hydroxymethyl radical 8 torsion A 482 717 235 0.673
CH2OH Hydroxymethyl radical 9 torsion A 234 449 215 0.521
HCCN cyanomethylene 5 Π 129 -526 -655 -0.245
CHCl2 dichloromethyl radical 4 A' 190 311 121 0.611
CH2Cl chloromethyl radical 4 B1 402 30 -372 13.570
NF3 Nitrogen trifluoride 1 A1 1032 624 -408 1.654
NF3 Nitrogen trifluoride 2 A1 647 1017 370 0.636
NF3 Nitrogen trifluoride 3 E 907 474 -433 1.915
NF3 Nitrogen trifluoride 4 E 492 900 408 0.546
BeBr2 Beryllium bromide 3 Πu 207 319 112 0.649
OClO- Chlorine dioxide anion 2 A1 418 324 -94 1.291
AsSe Arsenic monoselenide 1 Σ 280 414 134 0.676
Li2O dilithium oxide 3 Πu 112 -82 -193 -1.369
SiC2 Silicon dicarbide 3 B2 196 -77 -274 -2.540
C3 carbon trimer 3 Πu 63 -83 -146 -0.769
C4 Carbon tetramer 4 Πg 323 211 -112 1.531
C4 Carbon tetramer 5 Πu 160 104 -56 1.538
S3 Sulfur trimer 2 A1 281 557 276 0.504
SiH3Cl chlorosilane 5 E 954 2345 1391 0.407
SiH2D2 silane-d2 6 B1 2183 1676 -507 1.302
SiH2D2 silane-d2 8 B2 1601 2320 719 0.690
NH4 Ammonium radical 1 A1 2552 3042 490 0.839
B4H10 Tetraborane(10) 11 A1 785 587 -198 1.337
B4H10 Tetraborane(10) 12 A1 559 239 -320 2.343
B4H10 Tetraborane(10) 19 A2 662 439 -223 1.507
B4H10 Tetraborane(10) 36 B2 236 375 139 0.630
B5H9 pentaborane9 14 B2 2610 1743 -867 1.498
B5H9 pentaborane9 16 B2 1036 494 -542 2.097
B5H9 pentaborane9 19 E 2610 2007 -603 1.300
B5H9 pentaborane9 21 E 1634 1133 -501 1.443
B5H9 pentaborane9 22 E 1409 971 -438 1.451
CaS Calcium sulfide 1 Σ 459 376 -83 1.219
OPCl Phosphorus oxychloride 2 A' 308 495 187 0.622
OPCl Phosphorus oxychloride 3 A' 492 304 -188 1.620
CHFCl Chlorofluoromethyl radical 6 A 540 406 -134 1.330
H2CNCN cyanamide, methylene 3 A' 2208 3149 941 0.701
H2CNCN cyanamide, methylene 4 A' 1621 2241 620 0.723
SNO Nitrogen oxide sulfide 3 A' 792 508 -284 1.560
ONNO NO dimer 4 torsion A2 117 185 68 0.634
SSCl2 Thiothionyl chloride 5 A" 377 314 -63 1.202
AlNC Aluminum isocyanide 3 Π 100 170 70 0.587
SiH5+ Silane, protonated 1 A' 3694 4105 411 0.900