return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) 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 MP2=FULL/6-311G*
Calculated values were scaled by 0.9471.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.694
CH3COOH Acetic acid 18 A" 93 71 -22 1.310
CH3OH Methyl alcohol 12 A" 200 348 148 0.574
C6H6 Benzene 8 B2g 703 389 -314 1.807
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 328 114 0.653
C2H4+ Ethylene cation 4 Au 84 -101 -185 -0.836
C2H2 Acetylene 4 Πg 612 384 -228 1.592
CH3CCH propyne 10 E 328 239 -89 1.373
CHONH2 formamide 12 A" 289 -205 -494 -1.409
CBr2F2 Methane, dibromodifluoro- 3 A1 140 330 190 0.424
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 56 -19 1.332
CH3COOCH3 methyl acetate 27 A" 110 48 -62 2.307
CF2CCl2 difluorodichloroethylene 7 B1 1327 576 -751 2.303
CF2CCl2 difluorodichloroethylene 8 B1 989 317 -672 3.120
CF2CCl2 difluorodichloroethylene 11 B2 564 444 -120 1.269
CF2CCl2 difluorodichloroethylene 12 B2 323 181 -142 1.780
C9H8 Indene 40 A" 690 496 -194 1.391
C9H8 Indene 41 A" 549 377 -172 1.455
C6H5CN phenyl cyanide 19 B1 688 532 -156 1.294
C6H5CHO benzaldehyde 32 A" 688 419 -269 1.641
C6H4O2 parabenzoquinone 17 B2g 241 162 -79 1.486
C6H4O2 parabenzoquinone 30 B3u 109 83 -25 1.306
C3H6O 2-Propen-1-ol 24 A 188 109 -79 1.721
C6H5Cl chlorobenzene 18 B1 685 425 -260 1.611
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 151 -42 1.275
C5H8 Cyclopentene 18 A' 254 179 -75 1.420
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 520 169 0.675
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 334 -875 3.623
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 407 -126 1.309
C6F6 hexafluorobenzene 7 B2g 715 339 -376 2.106
C6F6 hexafluorobenzene 8 B2g 243 126 -117 1.929
C6F6 hexafluorobenzene 20 E2u 175 128 -47 1.364
NH2CN cyanamide 5 A' 408 665 257 0.614
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.009
C4H2 Diacetylene 7 Πg 482 -194 -676 -2.486
C4H2 Diacetylene 8 Πu 630 459 -171 1.374
C6H5F Fluorobenzene 18 B1 685 510 -175 1.342
CH3CCCH3 2-Butyne 16 E" 371 199 -172 1.868
C3H6O Oxetane 18 B1 90 -51 -140 -1.771
HCNO fulminic acid 5 Π 224 -345 -569 -0.650
C5H8 1,4-Pentadiene 16 A 137 293 156 0.468
HCCCl Chloroacetylene 5 Π 326 217 -109 1.504
CH3ONO Methyl nitrite 15 A" 186 84 -102 2.210
C6H8 1,4-Cyclohexadiene 19 B1u 108 61 -47 1.774
CO+ carbon monoxide cation 1 Σ 2214 2731 516 0.811
CaO Calcium monoxide 1 Σ 732 506 -226 1.447
LiOH lithium hydroxide 3 Π 257 402 146 0.638
NaOH sodium hydroxide 3 Π 300 209 -91 1.433
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.412
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.584
CN Cyano radical 1 Σ 2069 2710 642 0.763
C2H Ethynyl radical 2 Σ 1841 2341 500 0.786
C2H Ethynyl radical 3 Π 372 766 394 0.485
CH3 Methyl radical 2 A2" 606 410 -196 1.479
CH2OH Hydroxymethyl radical 8 A 482 703 221 0.686
CH2OH Hydroxymethyl radical 9 A 234 459 225 0.509
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 859 -277 1.323
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 116 -148 2.276
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 88 -270 4.045
CH3CO Acetyl radical 4 A' 1420 3024 1604 0.470
CHCl2 dichloromethyl radical 4 A' 190 306 116 0.621
CH2CHO Vinyloxy radical 10 A" 703 1016 313 0.692
C4H6 Methylenecyclopropane 17 B1 360 258 -102 1.393
C2Cl2 dichloroacetylene 4 Πg 333 178 -155 1.872
O2+ diatomic oxygen cation 1 Σg 1906 1412 -494 1.350
FOOF Perfluoroperoxide 3 A 360 233 -127 1.546
FOOF Perfluoroperoxide 4 A 202 129 -73 1.570
CaF2 Calcium difluoride 2 A1 120 59 -61 2.038
ZnCl Zinc monochloride 1 Σ 391 299 -91 1.305
PCl5 Phosphorus pentachloride 2 A1' 370 265 -105 1.396
O3 Ozone 3 B2 1042 2153 1111 0.484
NO Nitric oxide 1 Σ 1904 3347 1443 0.569
NO2 Nitrogen dioxide 3 B2 1618 2378 760 0.680
N2O4 Dinitrogen tetroxide 9 B2u 265 196 -69 1.354
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.384
VO Vanadium monoxide 1 Σ 1011 1820 809 0.556
Li2O dilithium oxide 3 Πu 112 58 -53 1.915
FO Oxygen monofluoride 1 Σ 1053 2329 1276 0.452
C3 carbon trimer 3 Πu 63 172 109 0.368
C5H5- cylopentadienyl anion 8 E1" 625 473 -152 1.321
C5H5- cylopentadienyl anion 14 E2" 600 450 -150 1.332
CaOH Calcium monohydroxide 2 Σ 353 625 272 0.565
CaOH Calcium monohydroxide 3 Π 609 361 -248 1.687
PS phosphorus sulfide 1 Σ 739 1288 549 0.574
ClNO2 Nitryl chloride 3 A1 364 280 -84 1.302
SF5Cl sulfur chloropentafluoride 5 B1 625 456 -169 1.370
SF5Cl sulfur chloropentafluoride 7 B2 505 309 -196 1.636
SF5Cl sulfur chloropentafluoride 11 E 397 243 -154 1.630
H3O+ hydronium cation 2 A1 954 720 -234 1.325
ZnH Zinc monohydride 1 Σ 1608 1070 -537 1.502
PO Phosphorus monoxide 1 Σ 1233 3543 2310 0.348
AlO Aluminum monoxide 1 Σ 979 744 -235 1.316
C2H4O4 Formic acid dimer 13 Au 1050 67 -983 15.619
FO2 Dioxygen monofluoride 1 A' 1487 2694 1207 0.552
FO2 Dioxygen monofluoride 2 A' 579 1229 650 0.471
FO2 Dioxygen monofluoride 3 A' 376 654 278 0.575
SCN thiocyanato radical 1 Σ 1942 2404 462 0.808
ClOO chloroperoxy radical 2 A' 414 1057 643 0.391
ClOO chloroperoxy radical 3 A' 201 487 286 0.413
H2POH Phosphinous acid 9 A" 375 271 -104 1.383
AsN Arsenic mononitride 1 Σ 1069 825 -243 1.295
Mg2 Magnesium diatomic 1 Σg 51 29 -22 1.747
ClOF3 Chlorine trifluoride oxide 5 A' 319 248 -71 1.288
ZnCH3 Zinc monomethyl 6 E 315 622 307 0.506
CH3BO Borane, methyloxo- 7 E 897 1428 531 0.628
ONONO Nitrosyl nitrite 9 B2 380 220 -160 1.725