return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

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 B3PW91/6-31G(2df,p)
Calculated values were scaled by 0.9614.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.633
CH3CONH2 Acetamide 20 A 259 169 -89 1.528
CH3COOH Acetic acid 18 A" 93 74 -19 1.254
CH3OH Methyl alcohol 12 A" 200 310 110 0.645
C2H6O2S Dimethyl sulfone 20 B1 262 201 -61 1.305
C2H4+ Ethylene cation 4 Au 84 -455 -539 -0.185
CHONH2 formamide 12 A" 289 169 -120 1.712
C3F8 perfluoropropane 13 A2 276 209 -67 1.319
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.681
CH3OCHO methyl formate 18 A" 130 104 -26 1.250
C4H8S Thiophene, tetrahydro- 5 A 1464 2949 1485 0.496
C4H8S Thiophene, tetrahydro- 6 A 1441 2948 1507 0.489
C4H8S Thiophene, tetrahydro- 7 A 1321 2933 1612 0.450
C4H8S Thiophene, tetrahydro- 8 A 1276 2932 1656 0.435
C4H8S Thiophene, tetrahydro- 12 A 888 1415 527 0.628
C4H8S Thiophene, tetrahydro- 13 A 829 1305 476 0.635
C4H8S Thiophene, tetrahydro- 14 A 822 1281 459 0.642
C4H8S Thiophene, tetrahydro- 15 A 678 1252 574 0.542
C4H8S Thiophene, tetrahydro- 16 A 472 1232 760 0.383
C4H8S Thiophene, tetrahydro- 17 A 290 1189 899 0.244
C5H8 Cyclopentene 18 A' 254 133 -121 1.910
C4H6O2 2,3-Butanedione 21 Bg 240 101 -139 2.370
C6H4 Benzyne 24 B2 472 349 -123 1.351
C5H12 Propane, 2,2-dimethyl- 12 T1 203 298 95 0.682
C2H3NO3 Oxamic acid 3 A' 2600 3481 881 0.747
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 21 A" 162 70 -92 2.316
C3H6O Oxetane 18 B1 90 61 -29 1.467
HCNO fulminic acid 5 Π 224 118 -106 1.897
Zn(CH3)2 dimethyl zinc 11 E' 134 99 -35 1.349
C6H6 Benzvalene 10 A1 996 745 -251 1.337
H2CS- thioformaldehyde anion 4 B1 450 -82 -532 -5.460
SiF2+ Silicon difluoride cation 2 A1 350 267 -83 1.310
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 347 -109 1.314
CH3OO methylperoxy radical 12 A" 170 124 -46 1.368
CH3 Methyl radical 2 A2" 606 455 -152 1.333
CH2OH Hydroxymethyl radical 9 A 234 421 187 0.555
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 861 -275 1.320
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 149 -115 1.773
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 100 -258 3.592
HCCN cyanomethylene 5 Π 129 -241 -370 -0.534
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.654
GaF3 Gallium trifluoride 4 E' 192 110 -82 1.746
CaF2 Calcium difluoride 2 A1 120 93 -27 1.295
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.440
C3 carbon trimer 3 Πu 63 128 65 0.494
Cu2 Copper dimer 1 Σg 265 405 141 0.653
TiO2 Titanium dioxide 1 A1 959 341 -618 2.812
ZnH2 Zinc hydride 3 Πu 633 391 -242 1.618
ClOO chloroperoxy radical 3 A' 201 87 -114 2.310
OPCl Phosphorus oxychloride 2 A' 308 486 178 0.634
OPCl Phosphorus oxychloride 3 A' 492 293 -199 1.676
H2OH2O water dimer 7 A' 143 206 63 0.695
H2OH2O water dimer 8 A' 103 155 52 0.664
H2OH2O water dimer 11 A" 108 168 60 0.643
H2OH2O water dimer 12 A" 88 55 -33 1.599
H2POH Phosphinous acid 9 A" 375 258 -117 1.454
Mg2 Magnesium diatomic 1 Σg 51 87 36 0.589
ZnCH3 Zinc monomethyl 6 E 315 574 259 0.549
ZnCN Zinc monocyanide 3 Π 212 129 -83 1.638