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 QCISD(T)/6-31G*
Calculated values were scaled by 0.9593.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 334 134 0.598
C2H4+ Ethylene cation 4 Au 84 -302 -386 -0.279
C2H2 Acetylene 4 Πg 612 314 -298 1.951
HCN+ hydrogen cyanide cation 3 Π 760 1877 1117 0.405
CH3CCH propyne 9 E 633 480 -153 1.320
CH3CCH propyne 10 E 328 210 -118 1.559
CHONH2 formamide 12 A" 289 -199 -488 -1.448
CH3COOCH3 methyl acetate 27 A" 110 57 -53 1.937
C10H8 naphthalene 27 B2g 770 419 -351 1.837
C10H8 naphthalene 28 B2g 461 294 -167 1.570
C6H5CN phenyl cyanide 19 B1 688 538 -150 1.279
C6H4O2 parabenzoquinone 17 B2g 241 178 -63 1.353
CHCCH2CH3 1-Butyne 22 A" 630 487 -143 1.293
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.781
C3H2N2 Malononitrile 6 A1 167 133 -34 1.256
CH2NN diazomethane 6 B1 406 318 -88 1.278
NH2CN cyanamide 5 A' 408 675 267 0.604
C4H2 Diacetylene 7 Πg 482 98 -384 4.905
C4H2 Diacetylene 8 Πu 630 422 -208 1.492
F2CCCF2 tetrafluoroallene 5 B2 2052 693 -1359 2.962
F2CCCF2 tetrafluoroallene 6 B2 1030 542 -488 1.900
F2CCCF2 tetrafluoroallene 7 B2 581 370 -211 1.572
F2CCCF2 tetrafluoroallene 11 E 90 65 -25 1.393
C6H5F Fluorobenzene 18 B1 685 511 -174 1.341
C3H6O Oxetane 18 B1 90 -71 -161 -1.258
HCNO fulminic acid 5 Π 224 -287 -511 -0.780
HCCCl Chloroacetylene 5 Π 326 152 -174 2.141
C6H6 Benzvalene 10 A1 996 746 -250 1.335
C2F2 difluoroacetylene 4 Πg 270 101 -169 2.661
H2CS- thioformaldehyde anion 4 B1 450 -174 -624 -2.588
HCCCN Cyanoacetylene 6 Π 499 396 -103 1.260
GeO2 Germanium dioxide 3 Πu 196 143 -53 1.369
NaOH sodium hydroxide 3 Π 300 149 -151 2.018
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 112 -59 1.526
FCO+ Carbonyl fluoride cation 3 Π 650 513 -137 1.267
CH3 Methyl radical 2 A2" 606 414 -192 1.464
CH2OH Hydroxymethyl radical 8 A 482 714 232 0.675
CH2OH Hydroxymethyl radical 9 A 234 433 199 0.540
HCCN cyanomethylene 5 Π 129 -507 -635 -0.254
HCCF Fluoroacetylene 5 Π 367 283 -84 1.298
CHCl2 dichloromethyl radical 4 A' 190 298 108 0.638
CuCl Copper monochloride 1 Σ 418 837 420 0.499
OClO- Chlorine dioxide anion 2 A1 418 313 -105 1.337
N2O3 Dinitrogen trioxide 9 A" 63 138 75 0.457
VO Vanadium monoxide 1 Σ 1011 1533 521 0.660
Li2O dilithium oxide 3 Πu 112 54 -57 2.058
C4 Carbon tetramer 4 Πg 323 198 -125 1.635
CuF Copper monofluoride 1 Σ 623 1197 574 0.520
CuH Copper monohydride 1 Σ 1941 3181 1240 0.610
SiH- silicon monohydride anion 1 Σ 2175 1737 -438 1.252
ZnH2 Zinc hydride 3 Πu 633 474 -159 1.334
Cl3- trichloride anion 2 Σu 327 257 -70 1.270
CaS Calcium sulfide 1 Σ 462 365 -97 1.266
OPCl Phosphorus oxychloride 2 A' 308 483 175 0.637
OPCl Phosphorus oxychloride 3 A' 492 292 -200 1.685
H2POH Phosphinous acid 9 A" 375 249 -126 1.508
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.323
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524
ZnCN Zinc monocyanide 3 Π 212 59 -153 3.611