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 CCD/6-311G*
Calculated values were scaled by 0.9551.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 345 145 0.580
C2H4+ Ethylene cation 4 Au 84 148 64 0.570
C2H2 Acetylene 4 Πg 612 434 -178 1.410
HCN+ hydrogen cyanide cation 1 Σ 3050 3457 407 0.882
HCN+ hydrogen cyanide cation 2 Σ 1800 2672 872 0.674
CHONH2 formamide 12 A" 289 -259 -547 -1.117
CH3COOCH3 methyl acetate 27 A" 110 64 -46 1.715
C10H8 naphthalene 12 Au 581 460 -121 1.264
C10H8 naphthalene 27 B2g 770 422 -348 1.827
C10H8 naphthalene 28 B2g 461 -191 -652 -2.412
C9H8 Indene 40 A" 690 533 -157 1.295
C6H4O2 parabenzoquinone 17 B2g 241 180 -61 1.337
C6H4O2 parabenzoquinone 30 B3u 109 84 -25 1.296
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.751
C6H5Cl chlorobenzene 18 B1 685 481 -203 1.423
C5H8 Cyclopentene 18 A' 254 163 -91 1.556
CH2NN diazomethane 6 B1 406 290 -116 1.400
NH2CN cyanamide 5 A' 408 686 278 0.595
C4H6O2 2,3-Butanedione 21 Bg 240 124 -116 1.936
C4H2 Diacetylene 7 Πg 482 -277 -759 -1.743
C3H6O Oxetane 18 B1 90 48 -42 1.888
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
HCCBr bromoacetylene 5 Π 295 231 -64 1.275
HCCCl Chloroacetylene 5 Π 326 229 -97 1.426
C6H8 1,4-Cyclohexadiene 19 B1u 108 85 -23 1.277
CO+ carbon monoxide cation 1 Σ 2214 2616 402 0.846
C6H6 Benzvalene 10 A1 996 741 -255 1.345
H2CS- thioformaldehyde anion 4 B1 450 55 -395 8.250
LiOH lithium hydroxide 3 Π 257 394 137 0.651
NaOH sodium hydroxide 3 Π 300 229 -71 1.309
ZnS Zinc sulfide 1 Σ 459 351 -108 1.307
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 332 -124 1.375
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 103 -68 1.668
CN Cyano radical 1 Σ 2069 2536 467 0.816
C2H Ethynyl radical 2 Σ 1841 2249 408 0.819
C2H Ethynyl radical 3 Π 372 727 356 0.511
CH3 Methyl radical 2 A2" 606 432 -175 1.405
CH2OH Hydroxymethyl radical 9 A 234 442 208 0.530
HCCN cyanomethylene 5 Π 129 -411 -540 -0.314
CHCl2 dichloromethyl radical 4 A' 190 304 114 0.626
C2Cl2 dichloroacetylene 4 Πg 333 180 -153 1.854
N2 Nitrogen diatomic 1 Σg 2359 1590 -769 1.483
CaF2 Calcium difluoride 2 A1 120 51 -69 2.338
ZnCl Zinc monochloride 1 Σ 391 298 -92 1.309
O3 Ozone 3 B2 1042 1643 601 0.634
NO Nitric oxide 1 Σ 1904 2816 912 0.676
NO2 Nitrogen dioxide 3 B2 1618 3545 1927 0.456
N2O3 Dinitrogen trioxide 9 A" 63 138 75 0.457
VO Vanadium monoxide 1 Σ 1011 1630 618 0.621
Li2O dilithium oxide 3 Πu 112 83 -29 1.350
C3 carbon trimer 3 Πu 63 104 40 0.613
SiH- silicon monohydride anion 1 Σ 2175 1686 -489 1.290
ZnH Zinc monohydride 1 Σ 1608 1108 -499 1.450
PO Phosphorus monoxide 1 Σ 1233 2488 1254 0.496
PN+ phosphorus nitride cation 1 Σ 1200 2283 1083 0.526
Cl3- trichloride anion 2 Σu 327 183 -144 1.788
OPCl Phosphorus oxychloride 2 A' 308 477 169 0.645
OPCl Phosphorus oxychloride 3 A' 492 305 -187 1.613
H2OH2O water dimer 11 A" 108 162 54 0.666
H2POH Phosphinous acid 9 A" 375 263 -112 1.425
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.488
ZnCH3 Zinc monomethyl 6 E 315 615 300 0.512
ClONO chlorine nitrite 4 A' 406 585 179 0.693
ONONO Nitrosyl nitrite 9 B2 380 578 198 0.657