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)/6-31G*
Calculated values were scaled by 0.9593.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 334 134 0.598
C2H4+ Ethylene cation 4 torsion Au 84 -302 -386 -0.279
C2H2 Acetylene 4 Πg 612 314 -298 1.951
HCN+ hydrogen cyanide cation 3 Π 760 1877 1117 0.405
CH3CCH propyne 9 E 633 480 -153 1.320
CH3CCH propyne 10 E 328 210 -118 1.559
CHONH2 formamide 12 torsion A" 289 -199 -488 -1.448
CH3COOCH3 methyl acetate 27 torsion A" 110 57 -53 1.937
C10H8 naphthalene 27 B2g 770 419 -351 1.837
C10H8 naphthalene 28 B2g 461 294 -167 1.570
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 493 -202 1.411
C6H5CN phenyl cyanide 19 B1 688 538 -150 1.279
C6H4Cl2 1,4-dichlorobenzene 16 B2g 687 491 -196 1.400
C6H4O2 parabenzoquinone 17 B2g 241 178 -63 1.353
CH3CH2CH2CH3 Butane 5 Ag 1442 415 -1027 3.479
CH3CH2CH2CH3 Butane 8 Ag 1151 828 -323 1.390
CH3CH2CH2CH3 Butane 36 Bu 271 2994 2723 0.091
CHCCH2CH3 1-Butyne 22 A" 630 487 -143 1.293
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 192 -2768 15.457
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 242 -2718 12.253
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 623 -823 2.322
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 742 -702 1.946
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1465 739 0.495
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1470 840 0.429
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 2995 2744 0.084
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3006 2804 0.067
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 111 -2899 27.209
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 746 -2264 4.037
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 959 -300 1.313
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3053 2290 0.250
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3078 2955 0.040
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.781
CH2ClCHO chloroacetaldehyde 15 A" 59 142 83 0.415
C3H2N2 Malononitrile 6 A1 167 133 -34 1.256
CHSNH2 thioformamide 12 A" 393 228 -165 1.724
C3F6 hexafluoropropene 21 A" 60 33 -27 1.842
CH2NN diazomethane 6 B1 406 318 -88 1.278
NH2CN cyanamide 5 torsion A' 408 675 267 0.604
C4H2 Diacetylene 7 Πg 482 98 -384 4.905
C4H2 Diacetylene 8 Πu 630 422 -208 1.492
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1022 -369 1.361
F2CCCF2 tetrafluoroallene 5 B2 2052 693 -1359 2.962
F2CCCF2 tetrafluoroallene 6 B2 1030 542 -488 1.900
F2CCCF2 tetrafluoroallene 7 B2 581 370 -211 1.572
F2CCCF2 tetrafluoroallene 11 E 90 65 -25 1.393
C6H5F Fluorobenzene 18 B1 685 511 -174 1.341
CH2CCH2 allene 1 A1 3015 1049 -1966 2.875
CH2CCH2 allene 8 E 3086 1450 -1636 2.128
C3H6O Oxetane 18 B1 90 -71 -161 -1.258
HCNO fulminic acid 5 torsion Π 224 -287 -511 -0.780
C6H4F2 1,4-difluorobenzene 16 B2g 692 497 -195 1.393
CBr4 Carbon tetrabromide 3 T2 672 260 -412 2.582
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 663 -2415 4.641
HCCCl Chloroacetylene 5 Π 326 152 -174 2.141
P(CH3)3 trimethylphosphine 22 E 259 193 -66 1.340
C6H6 Benzvalene 10 A1 996 746 -250 1.335
C2F2 difluoroacetylene 4 Πg 270 101 -169 2.661
H2CS- thioformaldehyde anion 4 B1 450 -174 -624 -2.588
CH2ClCCCl 1,3-dichloropropyne 9 A' 282 222 -60 1.271
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 173 -164 1.953
HCCCN Cyanoacetylene 6 Π 499 396 -103 1.260
GeO2 Germanium dioxide 3 Πu 196 143 -53 1.369
NaOH sodium hydroxide 3 torsion Π 300 149 -151 2.018
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 112 -59 1.526
FCO+ Carbonyl fluoride cation 3 Π 650 513 -137 1.267
CH3 Methyl radical 2 torsion A2" 606 414 -192 1.464
CH2OH Hydroxymethyl radical 8 torsion A 482 714 232 0.675
CH2OH Hydroxymethyl radical 9 torsion A 234 433 199 0.540
HCCN cyanomethylene 5 Π 129 -507 -635 -0.254
CHCl2 dichloromethyl radical 4 A' 190 298 108 0.638
CH2Cl chloromethyl radical 4 B1 402 -168 -570 -2.391
BF3+ boron trifluoride cation 5 B2 1791 1022 -769 1.753
CuCl Copper monochloride 1 Σ 414 837 423 0.495
BeBr2 Beryllium bromide 3 Πu 207 340 133 0.608
OClO- Chlorine dioxide anion 2 A1 418 313 -105 1.337
BCl3+ Boron Trichloride cation 3 E' 1104 651 -453 1.695
N2O3 Dinitrogen trioxide 9 torsion A" 63 138 75 0.457
VO Vanadium monoxide 1 Σ 1002 1533 531 0.653
Li2O dilithium oxide 3 Πu 112 54 -57 2.058
SiC2 Silicon dicarbide 3 B2 196 120 -77 1.641
S3 Sulfur trimer 2 A1 281 539 258 0.522
CuF Copper monofluoride 1 Σ 615 1197 582 0.514
SiH2D2 silane-d2 6 B1 2183 1576 -607 1.385
SiH2D2 silane-d2 8 B2 1601 2180 579 0.734
ZnH2 Zinc hydride 3 Πu 633 474 -159 1.334
B4H10 Tetraborane(10) 11 A1 785 566 -219 1.386
B4H10 Tetraborane(10) 12 A1 559 227 -332 2.460
B4H10 Tetraborane(10) 19 A2 662 417 -245 1.586
B4H10 Tetraborane(10) 36 B2 236 363 127 0.651
Cl3- trichloride anion 2 Σu 327 257 -70 1.270
B5H9 pentaborane9 13 B1 240 610 370 0.393
B5H9 pentaborane9 16 B2 1036 783 -253 1.323
B5H9 pentaborane9 18 B2 600 477 -123 1.257
B5H9 pentaborane9 22 E 1409 1083 -326 1.301
CaS Calcium sulfide 1 Σ 459 365 -94 1.256
OPCl Phosphorus oxychloride 2 A' 308 483 175 0.637
OPCl Phosphorus oxychloride 3 A' 492 292 -200 1.685
H2POH Phosphinous acid 9 A" 375 249 -126 1.508
Mg2 Magnesium diatomic 1 Σg 48 15 -32 3.112
CHFCl Chlorofluoromethyl radical 6 A 540 388 -152 1.390
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524
H2CNCN cyanamide, methylene 3 A' 2208 2984 776 0.740
H2CNCN cyanamide, methylene 4 A' 1621 2158 537 0.751
C2H3NO Nitrosoethylene 11 A' 490 332 -158 1.476
SNO Nitrogen oxide sulfide 1 A' 1527 487 -1040 3.133
ONNO NO dimer 4 torsion A2 117 183 66 0.640
ZnCN Zinc monocyanide 3 Π 212 59 -153 3.611