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 HF/6-31G(2df,p)
Calculated values were scaled by 0.9055.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 173 60 0.652
CH3OH Methyl alcohol 12 A" 200 298 98 0.671
CH3COCH3 Acetone 12 A2 77 58 -19 1.330
C2H4+ Ethylene cation 4 Au 84 360 276 0.233
CHONH2 formamide 12 A" 289 102 -187 2.825
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.680
C4H8S Thiophene, tetrahydro- 5 A 1464 2905 1441 0.504
C4H8S Thiophene, tetrahydro- 6 A 1441 2903 1462 0.496
C4H8S Thiophene, tetrahydro- 7 A 1321 2879 1558 0.459
C4H8S Thiophene, tetrahydro- 8 A 1276 2876 1600 0.444
C4H8S Thiophene, tetrahydro- 11 A 1023 1457 434 0.702
C4H8S Thiophene, tetrahydro- 12 A 888 1455 567 0.610
C4H8S Thiophene, tetrahydro- 13 A 829 1345 516 0.616
C4H8S Thiophene, tetrahydro- 14 A 822 1324 502 0.621
C4H8S Thiophene, tetrahydro- 15 A 678 1296 618 0.523
C4H8S Thiophene, tetrahydro- 16 A 472 1267 795 0.372
C4H8S Thiophene, tetrahydro- 17 A 290 1217 927 0.238
C5H8 Cyclopentene 18 A' 254 137 -117 1.856
C2H2N4 sym-tetrazine 18 B3u 254 368 114 0.690
NH2CN cyanamide 5 A' 408 629 221 0.648
C4H6O2 2,3-Butanedione 21 Bg 240 129 -111 1.857
C6H4 Benzyne 24 B2 472 235 -237 2.011
C2H3NO3 Oxamic acid 3 A' 2600 3482 882 0.747
C2H3NO3 Oxamic acid 21 A" 162 53 -109 3.054
HCNO fulminic acid 5 Π 224 535 311 0.419
Zn(CH3)2 dimethyl zinc 11 E' 134 99 -35 1.353
C5H8 1,4-Pentadiene 16 A 137 288 151 0.476
C2F2 difluoroacetylene 4 Πg 270 484 214 0.558
H2CS- thioformaldehyde anion 4 B1 450 -212 -662 -2.123
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C2H Ethynyl radical 3 Π 372 550 178 0.676
C2H+ Ethynyl cation 3 Π 550 865 316 0.635
CH3 Methyl radical 2 A2" 606 291 -316 2.087
CH2OH Hydroxymethyl radical 8 A 482 750 268 0.643
CH2OH Hydroxymethyl radical 9 A 234 368 134 0.636
ClCO carbonyl monochloride 3 A' 335 211 -124 1.589
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 850 -286 1.336
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 132 -132 2.006
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 90 -268 3.962
HCCN cyanomethylene 5 Π 129 -383 -512 -0.337
HNCS Isothiocyanic acid 5 A' 469 295 -174 1.590
CHCl2 dichloromethyl radical 4 A' 190 289 99 0.658
FOOF Perfluoroperoxide 2 A 630 1053 423 0.598
FOOF Perfluoroperoxide 3 A 360 520 160 0.692
FOOF Perfluoroperoxide 5 B 614 1046 432 0.587
GaF3 Gallium trifluoride 4 E' 192 130 -62 1.475
CaF2 Calcium difluoride 2 A1 120 65 -55 1.841
N2O4 Dinitrogen tetroxide 3 Ag 265 422 157 0.628
N2O3 Dinitrogen trioxide 6 A' 241 406 165 0.593
N2O3 Dinitrogen trioxide 7 A' 205 335 130 0.611
N2O3 Dinitrogen trioxide 8 A" 414 641 227 0.646
N2O3 Dinitrogen trioxide 9 A" 63 115 52 0.547
NS Mononitrogen monosulfide 1 Σ 1219 841 -378 1.450
VO Vanadium monoxide 1 Σ 1011 538 -473 1.878
Li2O dilithium oxide 3 Πu 112 166 54 0.672
C3 carbon trimer 3 Πu 63 114 51 0.555
SiP Silicon monophosphide 1 Σ 616 425 -191 1.449
PS phosphorus sulfide 1 Σ 739 491 -248 1.505
CP Carbon monophosphide 1 Σ 1240 923 -317 1.343
BH3CO Borane carbonyl 4 A1 691 512 -179 1.349
ZnH2 Zinc hydride 3 Πu 633 453 -179 1.396
AlO Aluminum monoxide 1 Σ 979 737 -243 1.329
ClOO chloroperoxy radical 2 A' 414 672 259 0.615
ClOO chloroperoxy radical 3 A' 201 426 225 0.473
PN+ phosphorus nitride cation 1 Σ 1200 771 -429 1.557
Cl3- trichloride anion 2 Σu 327 -97 -424 -3.370
OPCl Phosphorus oxychloride 2 A' 308 483 175 0.638
OPCl Phosphorus oxychloride 3 A' 492 312 -180 1.575
F3- trifluoride anion 2 Σu 550 -365 -915 -1.509
H2POH Phosphinous acid 9 A" 375 268 -107 1.401
Mg2 Magnesium diatomic 1 Σg 51 339 288 0.151
Al2 Aluminum diatomic 1 Σg 286 456 171 0.626
ZnCH3 Zinc monomethyl 6 E 315 567 252 0.555
H2COO dioxymethyl 6 A' 908 503 -405 1.805
NNS Nitrogen sulfide 2 Σ 752 563 -189 1.335
ClONO chlorine nitrite 4 A' 406 690 284 0.588
ONONO Nitrosyl nitrite 9 B2 380 714 334 0.532