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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 wB97X-D/6-31G*
Calculated values were scaled by 0.9485.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C4H10O Ethoxy ethane 20 A2 137 77 -60 1.784
CH3CONH2 Acetamide 20 A 259 133 -126 1.945
CH3COOH Acetic acid 18 torsion A" 93 -94 -187 -0.990
CH3OH Methyl alcohol 12 torsion A" 200 327 127 0.612
C2H4+ Ethylene cation 4 torsion Au 84 -375 -459 -0.224
CH3CHO+ acetaldehyde cation 15 A" 145 73 -72 1.985
CHONH2 formamide 12 torsion A" 289 154 -135 1.878
CH3SCH3+ dimethyl sulfide cation 15 B1 172 123 -49 1.400
C2F6 hexafluoroethane 4 torsion A1u 68 48 -20 1.402
C3F8 perfluoropropane 13 A2 276 212 -64 1.302
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 33 -42 2.272
CH3COCH2CH3 2-Butanone 32 torsion A" 106 24 -82 4.414
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -110 -197 -0.788
CH3COOCH3 methyl acetate 27 torsion A" 110 -104 -214 -1.053
CH3CH2CH2Br n-propyl bromide 27 torsion A" 133 101 -32 1.315
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.682
CH2ClCHO chloroacetaldehyde 15 torsion A 27 53 26 0.513
CH2ClCHO chloroacetaldehyde 15 A" 59 142 83 0.414
C5H12 Pentane 23 A2 131 90 -41 1.462
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 torsion A2 193 142 -51 1.361
C3F6 hexafluoropropene 21 A" 60 22 -38 2.674
C5H8 Cyclopentene 18 torsion A' 254 149 -105 1.700
C5H8 Bicyclo[1.1.1]pentane 8 A2" 2976 1221 -1755 2.438
C5H8 Bicyclo[1.1.1]pentane 9 A2" 1220 832 -387 1.466
CF3CHF2 pentafluoroethane 18 torsion A" 75 57 -18 1.317
C6F6 hexafluorobenzene 7 B2g 719 522 -197 1.376
C4H6O2 2,3-Butanedione 16 torsion Au 48 -45 -93 -1.068
C4H6O2 2,3-Butanedione 21 torsion Bg 240 10 -230 23.209
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1007 -384 1.381
C5H12 Propane, 2,2-dimethyl- 12 T1 203 339 136 0.599
C2H3NO3 Oxamic acid 3 A' 2600 3459 859 0.752
C2H3NO3 Oxamic acid 21 A" 162 64 -98 2.540
C3H6O Oxetane 18 B1 90 -55 -144 -1.643
C3O2 Carbon suboxide 7 Πu 61 109 48 0.561
CH3COF Acetyl fluoride 15 torsion A" 123 33 -90 3.777
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 678 -2401 4.543
C5H8 1,4-Pentadiene 16 A 137 274 137 0.501
C5H8 1,4-Pentadiene 17 torsion A 102 70 -32 1.462
C5H8 1,4-Pentadiene 17 torsion A 102 70 -32 1.462
C5H8 1,4-Pentadiene 33 torsion B 331 89 -242 3.714
C6H6 Benzvalene 10 A1 996 745 -251 1.337
C6H10 2-Hexyne 41 A" 88 46 -42 1.901
C5H8O Methyl cyclopropyl ketone 35 A" 125 65 -60 1.917
H2CS- thioformaldehyde anion 4 B1 450 -87 -537 -5.182
NaOH sodium hydroxide 3 torsion Π 300 59 -241 5.096
CFCl2 dichlorofluoromethyl radical 2 A' 747 588 -159 1.271
C2H+ Ethynyl cation 3 Π 550 941 392 0.584
CH3OO methylperoxy radical 12 torsion A" 170 116 -54 1.468
CH3 Methyl radical 2 torsion A2" 606 438 -169 1.385
CH2OH Hydroxymethyl radical 9 torsion A 234 429 195 0.545
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 860 -276 1.321
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 125 -139 2.119
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 80 -278 4.490
HCCN cyanomethylene 5 Π 129 -313 -442 -0.412
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.645
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.292
CH2Cl chloromethyl radical 4 B1 402 -56 -458 -7.150
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.270
BF3+ boron trifluoride cation 5 B2 1791 673 -1117 2.659
BeBr2 Beryllium bromide 3 Πu 207 336 129 0.617
BCl3+ Boron Trichloride cation 3 E' 1104 767 -337 1.440
N2O3 Dinitrogen trioxide 9 torsion A" 63 137 74 0.461
C3O Tricarbon monoxide 5 Π 109 172 63 0.633
AsSe Arsenic monoselenide 1 Σ 280 415 135 0.674
SiC2 Silicon dicarbide 3 B2 196 133 -64 1.481
C3 carbon trimer 3 Πu 63 157 93 0.405
S3 Sulfur trimer 2 A1 281 585 304 0.480
SiH2D2 silane-d2 6 B1 2183 1540 -643 1.418
SiH2D2 silane-d2 8 B2 1601 2131 530 0.751
ZnH2 Zinc hydride 3 Πu 633 488 -145 1.297
ClOO chloroperoxy radical 2 A' 414 227 -187 1.824
ClOO chloroperoxy radical 3 A' 201 106 -96 1.903
Cl3- trichloride anion 2 Σu 327 227 -100 1.442
B5H9 pentaborane9 13 B1 240 592 352 0.406
B5H9 pentaborane9 16 B2 1036 779 -257 1.330
B5H9 pentaborane9 22 E 1409 1058 -351 1.332
OPCl Phosphorus oxychloride 2 A' 308 492 184 0.625
OPCl Phosphorus oxychloride 3 A' 492 296 -196 1.660
H2OH2O water dimer 7 A' 143 229 86 0.626
H2OH2O water dimer 12 A" 88 -41 -129 -2.147
H2POH Phosphinous acid 9 A" 375 274 -101 1.370
CHFCl Chlorofluoromethyl radical 6 A 540 389 -151 1.389
ZnCH3 Zinc monomethyl 6 E 315 596 281 0.529
NH2NN+ hydrazoic acid, protonated 6 A' 489 289 -200 1.695
H2CNCN cyanamide, methylene 3 A' 2208 2965 757 0.745
H2CNCN cyanamide, methylene 4 A' 1621 2245 624 0.722
C2H3NO Nitrosoethylene 11 A' 490 332 -158 1.475
SNO Nitrogen oxide sulfide 3 A' 792 492 -300 1.609
ZnCN Zinc monocyanide 3 Π 212 82 -130 2.581