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 mPW1PW91/6-31G**
Calculated values were scaled by 0.9515.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.645
CH3COCH3 Acetone 12 A2 77 32 -45 2.393
C2H4+ Ethylene cation 4 Au 84 -424 -508 -0.199
CH3CONH2 Acetamide 20 A 259 152 -107 1.700
CHONH2 formamide 12 A" 289 199 -90 1.451
C2F6 hexafluoroethane 4 A1u 68 47 -21 1.451
C3F8 perfluoropropane 13 A2 276 207 -69 1.331
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.191
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.697
C4H8S Thiophene, tetrahydro- 5 A 1464 2948 1484 0.497
C4H8S Thiophene, tetrahydro- 6 A 1441 2948 1507 0.489
C4H8S Thiophene, tetrahydro- 7 A 1321 2932 1611 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2931 1655 0.435
C4H8S Thiophene, tetrahydro- 11 A 1023 1423 400 0.719
C4H8S Thiophene, tetrahydro- 12 A 888 1421 533 0.625
C4H8S Thiophene, tetrahydro- 13 A 829 1310 481 0.633
C4H8S Thiophene, tetrahydro- 14 A 822 1285 463 0.640
C4H8S Thiophene, tetrahydro- 15 A 678 1259 581 0.539
C4H8S Thiophene, tetrahydro- 16 A 472 1236 764 0.382
C4H8S Thiophene, tetrahydro- 17 A 290 1194 904 0.243
C5H8 Cyclopentene 18 A' 254 140 -114 1.812
C6F6 hexafluorobenzene 7 B2g 719 513 -206 1.403
C4H6O2 2,3-Butanedione 21 Bg 240 94 -146 2.546
C5H12 Propane, 2,2-dimethyl- 12 T1 203 302 99 0.673
C2H3NO3 Oxamic acid 3 A' 2600 3471 871 0.749
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.275
C2H3NO3 Oxamic acid 21 A" 162 69 -93 2.363
C3H6O Oxetane 18 B1 90 46 -44 1.969
C3O2 Carbon suboxide 7 Πu 61 114 53 0.535
C5H8 1,4-Pentadiene 16 A 137 283 146 0.485
C6H6 Benzvalene 10 A1 996 746 -250 1.335
H2CS- thioformaldehyde anion 4 B1 450 49 -401 9.230
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.697
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
HCCN cyanomethylene 5 Π 129 -288 -417 -0.448
CH3OO methylperoxy radical 12 A" 170 128 -42 1.328
CH3 Methyl radical 2 A2" 606 445 -161 1.363
CH2OH Hydroxymethyl radical 9 A 234 413 179 0.567
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 864 -272 1.315
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 147 -117 1.795
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 99 -259 3.602
CHCl2 dichloromethyl radical 4 A' 190 296 106 0.642
C4H6 Methylenecyclopropane 17 B1 360 284 -76 1.270
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.450
C3O Tricarbon monoxide 5 Π 109 174 65 0.626
C3 carbon trimer 3 Πu 63 142 78 0.447
TiO2 Titanium dioxide 1 A1 959 340 -619 2.823
H3O+ hydronium cation 2 A1 954 754 -200 1.265
ZnH2 Zinc hydride 3 Πu 633 479 -153 1.320
ClOO chloroperoxy radical 2 A' 414 278 -136 1.488
ClOO chloroperoxy radical 3 A' 201 121 -80 1.661
OPCl Phosphorus oxychloride 2 A' 308 485 177 0.635
OPCl Phosphorus oxychloride 3 A' 492 292 -200 1.682
H2OH2O water dimer 7 A' 143 211 68 0.679
H2OH2O water dimer 8 A' 103 148 45 0.694
H2OH2O water dimer 11 A" 108 168 60 0.643
H2POH Phosphinous acid 9 A" 375 254 -122 1.479
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.595
ZnCH3 Zinc monomethyl 6 E 315 595 280 0.529
ZnCN Zinc monocyanide 3 Π 212 68 -144 3.134