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/6-31G*
Calculated values were scaled by 0.9523.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 168 55 0.672
CH3OH Methyl alcohol 12 torsion A" 200 333 133 0.601
CH3COCH3 Acetone 12 torsion A2 77 59 -18 1.316
C6H6 Benzene 8 B2g 703 554 -149 1.268
C2H4+ Ethylene cation 4 torsion Au 84 -253 -337 -0.332
C2H2 Acetylene 4 Πg 612 398 -214 1.537
CH3CCH propyne 10 E 328 253 -75 1.295
CHONH2 formamide 12 torsion A" 289 -182 -471 -1.585
CH3SCH3+ dimethyl sulfide cation 15 B1 172 133 -39 1.295
C3F8 perfluoropropane 13 A2 276 215 -61 1.286
CH3COOCH3 methyl acetate 27 torsion A" 110 73 -37 1.504
C10H8 naphthalene 27 B2g 770 433 -337 1.779
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 539 -156 1.289
C6H4Cl2 1,4-dichlorobenzene 16 B2g 687 536 -151 1.281
C6H4O2 parabenzoquinone 17 B2g 241 183 -58 1.316
C6H4O2 parabenzoquinone 30 B3u 109 83 -25 1.303
CH3CH2CH2CH3 Butane 5 Ag 1442 415 -1027 3.476
CH3CH2CH2CH3 Butane 8 Ag 1151 827 -324 1.391
CH3CH2CH2CH3 Butane 36 Bu 271 2986 2715 0.091
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 192 -2768 15.429
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 243 -2717 12.202
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 628 -818 2.302
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 749 -695 1.929
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1464 738 0.496
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1467 837 0.429
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 2991 2740 0.084
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3001 2799 0.067
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 111 -2899 27.171
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 746 -2264 4.037
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 961 -298 1.311
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3047 2284 0.250
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3071 2948 0.040
C3H6O 2-Propen-1-ol 24 A 188 106 -83 1.781
CH2ClCHO chloroacetaldehyde 15 A" 59 145 86 0.406
CHSNH2 thioformamide 12 A" 393 254 -139 1.548
C3F6 hexafluoropropene 21 A" 60 33 -27 1.842
C5H8 Cyclopentene 18 torsion A' 254 159 -95 1.597
NH2CN cyanamide 5 torsion A' 408 659 251 0.619
C4H6O2 2,3-Butanedione 21 torsion Bg 240 121 -119 1.977
C4H2 Diacetylene 7 Πg 482 332 -150 1.450
C4H2 Diacetylene 8 Πu 630 485 -145 1.299
C2H3NO3 Oxamic acid 3 A' 2600 3454 854 0.753
C2H3NO3 Oxamic acid 16 A" 984 770 -214 1.279
C2H3NO3 Oxamic acid 20 A" 315 236 -79 1.335
C2H3NO3 Oxamic acid 21 A" 162 38 -124 4.304
CH3CCCH3 2-Butyne 16 E" 371 226 -145 1.645
C3H6O Oxetane 18 B1 90 -52 -141 -1.739
HCNO fulminic acid 5 torsion Π 224 -37 -261 -6.129
C6H4F2 1,4-difluorobenzene 16 B2g 692 539 -153 1.283
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 674 -2405 4.569
C5H8 1,4-Pentadiene 16 A 137 288 151 0.476
HCCCl Chloroacetylene 5 Π 326 217 -109 1.503
P(CH3)3 trimethylphosphine 22 E 259 195 -64 1.330
C6H6 Benzvalene 10 A1 996 750 -246 1.327
C2F2 difluoroacetylene 4 Πg 270 197 -73 1.368
H2CS- thioformaldehyde anion 4 B1 450 -164 -614 -2.751
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 215 -122 1.571
GeO2 Germanium dioxide 3 Πu 196 152 -43 1.285
NaOH sodium hydroxide 3 torsion Π 300 100 -200 2.999
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.359
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 111 -60 1.547
CH3 Methyl radical 2 torsion A2" 606 412 -195 1.472
CH2OH Hydroxymethyl radical 8 torsion A 482 712 230 0.677
CH2OH Hydroxymethyl radical 9 torsion A 234 426 192 0.549
HCCN cyanomethylene 5 Π 129 -491 -620 -0.263
CHCl2 dichloromethyl radical 4 A' 190 298 108 0.637
C4H6 Methylenecyclopropane 17 B1 360 271 -89 1.329
CH2Cl chloromethyl radical 4 B1 402 -165 -567 -2.432
C2Cl2 dichloroacetylene 4 Πg 333 180 -153 1.853
BF3+ boron trifluoride cation 5 B2 1791 401 -1390 4.466
N2 Nitrogen diatomic 1 Σg 2330 1631 -699 1.428
CuCl Copper monochloride 1 Σ 414 266 -148 1.557
FOOF Perfluoroperoxide 1 A 1210 957 -253 1.264
BeBr2 Beryllium bromide 3 Πu 207 339 132 0.611
OClO- Chlorine dioxide anion 2 A1 418 323 -95 1.296
BCl3+ Boron Trichloride cation 3 E' 1104 715 -389 1.544
N2O3 Dinitrogen trioxide 9 torsion A" 63 134 71 0.469
NO3 Nitrogen trioxide 3 E' 1492 1108 -385 1.347
NO3 Nitrogen trioxide 4 E' 360 119 -241 3.033
NaO2 Sodium superoxide 3 B2 333 239 -94 1.391
Li2O dilithium oxide 3 Πu 112 43 -69 2.616
SiC2 Silicon dicarbide 3 B2 196 79 -117 2.483
C3 carbon trimer 3 Πu 63 47 -16 1.351
TiO Titanium monoxide 1 Σ 1000 4454 3454 0.225
C4 Carbon tetramer 4 Πg 323 255 -68 1.267
CuF Copper monofluoride 1 Σ 615 477 -138 1.290
SiH2D2 silane-d2 6 B1 2183 1569 -614 1.392
SiH2D2 silane-d2 8 B2 1601 2170 569 0.738
ZnH2 Zinc hydride 3 Πu 633 473 -159 1.337
BrO+ Bromine monoxide cation 1 Σ 840 583 -257 1.441
B4H10 Tetraborane(10) 11 A1 785 561 -224 1.398
B4H10 Tetraborane(10) 12 A1 559 227 -332 2.463
B4H10 Tetraborane(10) 19 A2 662 417 -245 1.588
B4H10 Tetraborane(10) 36 B2 236 360 124 0.655
Cl3- trichloride anion 2 Σu 327 222 -105 1.476
B5H9 pentaborane9 13 B1 240 609 369 0.394
B5H9 pentaborane9 16 B2 1036 785 -251 1.319
B5H9 pentaborane9 22 E 1409 1084 -325 1.300
CaS Calcium sulfide 1 Σ 459 363 -95 1.263
OPCl Phosphorus oxychloride 2 A' 308 488 180 0.631
OPCl Phosphorus oxychloride 3 A' 492 297 -195 1.657
H2POH Phosphinous acid 9 A" 375 251 -125 1.497
Mg2 Magnesium diatomic 1 Σg 48 299 251 0.160
CHFCl Chlorofluoromethyl radical 6 A 540 389 -151 1.388
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524
H2CNCN cyanamide, methylene 3 A' 2208 2983 775 0.740
H2CNCN cyanamide, methylene 4 A' 1621 2203 582 0.736
SNO Nitrogen oxide sulfide 3 A' 792 490 -302 1.616
ONNO NO dimer 2 A1 239 352 113 0.680
ONNO NO dimer 3 A1 135 322 187 0.418
ONNO NO dimer 4 torsion A2 117 217 100 0.539
ONNO NO dimer 6 B2 429 679 250 0.632
ZnCN Zinc monocyanide 3 Π 212 81 -131 2.605