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 B1B95/cc-pVTZ
Calculated values were scaled by 0.9571.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 174 61 0.648
CH3CONH2 Acetamide 20 A 259 161 -98 1.605
CH3OH Methyl alcohol 12 A" 200 292 92 0.684
C2H6O2S Dimethyl sulfone 20 B1 262 201 -61 1.306
C2H4+ Ethylene cation 4 Au 84 -497 -582 -0.169
CHONH2 formamide 12 A" 289 208 -81 1.388
CH3COCl Acetyl Chloride 15 A" 166 130 -36 1.281
C3F8 perfluoropropane 13 A2 276 210 -66 1.315
CH3COOCH3 methyl acetate 26 A" 136 99 -37 1.375
CH3COOCH3 methyl acetate 27 A" 110 47 -63 2.341
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.691
C4H8S Thiophene, tetrahydro- 5 A 1464 2947 1483 0.497
C4H8S Thiophene, tetrahydro- 6 A 1441 2947 1506 0.489
C4H8S Thiophene, tetrahydro- 7 A 1321 2931 1610 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2930 1654 0.436
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 1283 461 0.641
C4H8S Thiophene, tetrahydro- 15 A 678 1252 574 0.542
C4H8S Thiophene, tetrahydro- 16 A 472 1233 761 0.383
C4H8S Thiophene, tetrahydro- 17 A 290 1190 900 0.244
C5H8 Cyclopentene 18 A' 254 147 -107 1.729
C4H6O2 2,3-Butanedione 21 Bg 240 100 -140 2.390
C5H12 Propane, 2,2-dimethyl- 12 T1 203 295 92 0.688
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C2H3NO3 Oxamic acid 15 A' 328 251 -77 1.307
C2H3NO3 Oxamic acid 21 A" 162 68 -94 2.389
C3H6O Oxetane 18 B1 90 -24 -113 -3.812
C3O2 Carbon suboxide 7 Πu 61 40 -21 1.538
CH3OC2H5 Ethane, methoxy- 29 A" 248 197 -51 1.256
C5H8 1,4-Pentadiene 16 A 137 284 147 0.483
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.269
C6H6 Benzvalene 10 A1 996 744 -252 1.339
H2CS- thioformaldehyde anion 4 B1 450 185 -265 2.434
SiF2+ Silicon difluoride cation 2 A1 350 272 -78 1.289
CH3C(SCH3)HCH3 Propane, 2-(methylthio)- 37 A 215 170 -45 1.262
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.695
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 347 -109 1.314
CH3 Methyl radical 2 A2" 606 479 -127 1.266
CH2OH Hydroxymethyl radical 9 A 234 414 180 0.565
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.316
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 147 -117 1.802
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 98 -260 3.652
HCCN cyanomethylene 5 Π 129 -198 -327 -0.652
CHCl2 dichloromethyl radical 4 A' 190 290 100 0.654
C4H6 Methylenecyclopropane 17 B1 360 286 -74 1.259
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.441
Li2O dilithium oxide 1 Σg 779 -36042 -36822 -0.022
Li2O dilithium oxide 3 Πu 112 -210 -321 -0.533
C3 carbon trimer 3 Πu 63 50 -14 1.280
ClOO chloroperoxy radical 2 A' 414 293 -121 1.414
ClOO chloroperoxy radical 3 A' 201 109 -93 1.851
Cl3- trichloride anion 2 Σu 327 250 -77 1.306
OPCl Phosphorus oxychloride 2 A' 308 489 181 0.630
OPCl Phosphorus oxychloride 3 A' 492 297 -195 1.655
H2POH Phosphinous acid 9 A" 375 261 -115 1.439