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(2df,p)
Calculated values were scaled by 0.9547.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.638
CH3CONH2 Acetamide 20 A 259 168 -91 1.542
CH3COOH Acetic acid 18 A" 93 71 -22 1.303
CH3OH Methyl alcohol 12 A" 200 309 109 0.646
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.269
C2H4+ Ethylene cation 4 Au 84 -427 -512 -0.197
CHONH2 formamide 12 A" 289 168 -121 1.718
C3F8 perfluoropropane 13 A2 276 209 -67 1.323
C3H6O 2-Propen-1-ol 24 A 188 112 -77 1.687
C4H8S Thiophene, tetrahydro- 5 A 1464 2946 1482 0.497
C4H8S Thiophene, tetrahydro- 6 A 1441 2946 1505 0.489
C4H8S Thiophene, tetrahydro- 7 A 1321 2930 1609 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2929 1653 0.436
C4H8S Thiophene, tetrahydro- 12 A 888 1412 524 0.629
C4H8S Thiophene, tetrahydro- 13 A 829 1304 475 0.636
C4H8S Thiophene, tetrahydro- 14 A 822 1280 458 0.642
C4H8S Thiophene, tetrahydro- 15 A 678 1251 573 0.542
C4H8S Thiophene, tetrahydro- 16 A 472 1230 758 0.384
C4H8S Thiophene, tetrahydro- 17 A 290 1188 898 0.244
C5H8 Cyclopentene 18 A' 254 135 -119 1.878
C6F6 hexafluorobenzene 7 B2g 719 563 -156 1.276
C4H6O2 2,3-Butanedione 21 Bg 240 101 -139 2.373
C6H4 Benzyne 24 B2 472 344 -128 1.374
C5H12 Propane, 2,2-dimethyl- 12 T1 203 298 95 0.682
C2H3NO3 Oxamic acid 3 A' 2600 3480 880 0.747
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 21 A" 162 70 -92 2.313
C3H6O Oxetane 18 B1 90 57 -33 1.578
Zn(CH3)2 dimethyl zinc 11 E' 134 100 -34 1.335
C6H6 Benzvalene 10 A1 996 746 -250 1.336
H2CS- thioformaldehyde anion 4 B1 450 -49 -499 -9.139
NaOH sodium hydroxide 3 Π 300 127 -173 2.368
SiF2+ Silicon difluoride cation 2 A1 350 268 -82 1.305
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.316
CH3OO methylperoxy radical 12 A" 170 125 -45 1.362
CH3 Methyl radical 2 A2" 606 451 -156 1.346
CH2OH Hydroxymethyl radical 9 A 234 416 182 0.563
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 860 -276 1.321
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 148 -116 1.790
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 98 -260 3.644
HCCN cyanomethylene 5 Π 129 -247 -376 -0.521
CHCl2 dichloromethyl radical 4 A' 190 290 100 0.654
GaF3 Gallium trifluoride 4 E' 192 110 -82 1.744
CaF2 Calcium difluoride 2 A1 120 92 -28 1.307
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.439
Li2O dilithium oxide 3 Πu 112 160 48 0.699
C3 carbon trimer 3 Πu 63 124 60 0.513
TiO2 Titanium dioxide 1 A1 959 339 -620 2.826
ZnH2 Zinc hydride 3 Πu 633 397 -236 1.594
ClOO chloroperoxy radical 2 A' 414 304 -109 1.360
ClOO chloroperoxy radical 3 A' 201 124 -77 1.622
OPCl Phosphorus oxychloride 2 A' 308 489 181 0.629
OPCl Phosphorus oxychloride 3 A' 492 296 -196 1.663
H2OH2O water dimer 7 A' 143 208 65 0.688
H2OH2O water dimer 8 A' 103 152 49 0.676
H2OH2O water dimer 11 A" 108 166 58 0.651
H2OH2O water dimer 12 A" 88 47 -41 1.861
H2POH Phosphinous acid 9 A" 375 260 -116 1.446
Mg2 Magnesium diatomic 1 Σg 51 88 37 0.578
ZnCH3 Zinc monomethyl 6 E 315 571 256 0.551
ZnCN Zinc monocyanide 3 Π 212 132 -80 1.606