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 B3LYP/6-31+G**
Calculated values were scaled by 0.9642.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.636
CH3COOH Acetic acid 18 A" 93 66 -27 1.415
CH3OH Methyl alcohol 12 A" 200 304 104 0.658
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.270
C2H4+ Ethylene cation 4 Au 84 -455 -539 -0.185
CH3COCl Acetyl Chloride 15 A" 166 123 -43 1.345
C3F8 perfluoropropane 13 A2 276 215 -61 1.284
CH3COOCH3 methyl acetate 27 A" 110 27 -83 4.034
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.706
C4H8S Thiophene, tetrahydro- 5 A 1464 2955 1491 0.495
C4H8S Thiophene, tetrahydro- 6 A 1441 2955 1514 0.488
C4H8S Thiophene, tetrahydro- 7 A 1321 2934 1613 0.450
C4H8S Thiophene, tetrahydro- 8 A 1276 2933 1657 0.435
C4H8S Thiophene, tetrahydro- 11 A 1023 1436 413 0.713
C4H8S Thiophene, tetrahydro- 12 A 888 1434 546 0.619
C4H8S Thiophene, tetrahydro- 13 A 829 1314 485 0.631
C4H8S Thiophene, tetrahydro- 14 A 822 1293 471 0.636
C4H8S Thiophene, tetrahydro- 15 A 678 1264 586 0.537
C4H8S Thiophene, tetrahydro- 16 A 472 1243 771 0.380
C4H8S Thiophene, tetrahydro- 17 A 290 1196 906 0.242
C4H6O2 2,3-Butanedione 21 Bg 240 107 -133 2.253
C5H12 Propane, 2,2-dimethyl- 12 T1 203 300 97 0.676
C2H3NO3 Oxamic acid 3 A' 2600 3465 865 0.750
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.266
C2H3NO3 Oxamic acid 17 A" 815 647 -168 1.259
C2H3NO3 Oxamic acid 21 A" 162 63 -99 2.587
C3H6O Oxetane 18 B1 90 44 -46 2.039
C3O2 Carbon suboxide 7 Πu 61 167 106 0.366
C5H8 1,4-Pentadiene 16 A 137 290 153 0.472
HCCBr bromoacetylene 5 Π 295 450 155 0.656
C6H6 Benzvalene 10 A1 996 740 -256 1.346
H2CS- thioformaldehyde anion 4 B1 450 273 -177 1.646
C4H6O Cyclobutanone 12 A2 1163 916 -247 1.270
C4H6O Cyclobutanone 13 A2 909 607 -302 1.497
C4H6O Cyclobutanone 20 B1 63 12 -51 5.447
NaOH sodium hydroxide 3 Π 300 230 -70 1.306
SiF2+ Silicon difluoride cation 2 A1 350 268 -82 1.306
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.691
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 348 -108 1.312
CH3OO methylperoxy radical 12 A" 170 128 -42 1.324
C4H9N Cyclobutylamine 21 A' 174 137 -37 1.275
CH2OH Hydroxymethyl radical 9 A 234 412 178 0.568
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 864 -272 1.315
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 145 -119 1.818
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 101 -257 3.534
HCCN cyanomethylene 5 Π 129 -240 -369 -0.538
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.648
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.270
OClO- Chlorine dioxide anion 2 A1 418 320 -98 1.308
N2O3 Dinitrogen trioxide 9 A" 63 131 68 0.479
SF5 Sulfur pentafluoride 9 E 387 300 -87 1.291
C3O Tricarbon monoxide 5 Π 109 201 92 0.543
C3 carbon trimer 3 Πu 63 179 116 0.354
H3O+ hydronium cation 2 A1 954 738 -216 1.293
ClOO chloroperoxy radical 2 A' 414 289 -124 1.430
ClOO chloroperoxy radical 3 A' 201 111 -90 1.813
Cl3- trichloride anion 2 Σu 327 254 -73 1.287
OPCl Phosphorus oxychloride 2 A' 308 461 153 0.668
OPCl Phosphorus oxychloride 3 A' 492 283 -209 1.736
H2OH2O water dimer 8 A' 103 164 61 0.628
H2OH2O water dimer 11 A" 108 174 66 0.620
H2OH2O water dimer 12 A" 88 137 49 0.641
H2POH Phosphinous acid 9 A" 375 248 -127 1.511
ZnCH3 Zinc monomethyl 6 E 315 585 270 0.538
ClONO chlorine nitrite 5 A' 270 216 -54 1.248
ZnCH2 Zinc methylene 2 A1 1342 2980 1639 0.450
ZnCH2 Zinc methylene 3 A1 514 1268 754 0.405