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XIII.F.2. (III.B.7.b.) (IV.C.7.) (XVIII.B.2.)

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
C2H2 Acetylene 4 Πg 612 434 -178 1.410
HCN+ hydrogen cyanide cation 2 Σ 1800 2672 872 0.674
CH3COOCH3 methyl acetate 27 A" 110 64 -46 1.715
C6H4O2 parabenzoquinone 30 B3u 109 84 -25 1.296
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
C6H5F Fluorobenzene 18 B1 685 549 -136 1.248
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
COBr2 Carbonic dibromide 6 B2 512 349 -163 1.469
CO+ carbon monoxide cation 1 Σ 2214 2616 402 0.846
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' 144 215 71 0.668
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 332 -124 1.373
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 102 -69 1.673
C2H5 Ethyl radical 9 A' 528 430 -98 1.227
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
C2Cl2 dichloroacetylene 4 Πg 333 180 -153 1.854
AsH3+ Arsine cation 2 A1 452 651 199 0.695
Li2O dilithium oxide 3 Πu 112 83 -29 1.350
C3 carbon trimer 3 Πu 63 103 40 0.613
CaOH Calcium monohydroxide 2 Σ 353 630 277 0.561
CaOH Calcium monohydroxide 3 Π 609 369 -240 1.649
Cu2 Copper dimer 1 Σg 265 218 -46 1.212
H3O+ hydronium 2 A1 954 770 -184 1.239
ZnH Zinc monohydride 1 Σ 1608 1108 -499 1.450
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.488
ZnCH3 Zinc monomethyl 6 E 315 615 300 0.512
C2Cl2+ dichloroacetylene cation 5 Πu 233 180 -53 1.294
ZnCl Zinc monochloride 1 Σ 391 298 -92 1.309
NO Nitric oxide 1 Σ 1904 2817 913 0.676
AlO Aluminum monoxide 1 Σ 979 780 -200 1.256
CH3OH Methyl alcohol 12 A" 200 345 145 0.580
CH3NH2 methyl amine 14 A" 1195 951 -244 1.257
HCN+ hydrogen cyanide cation 1 Σ 3050 3457 407 0.882
C6H4O2 parabenzoquinone 17 B2g 241 180 -61 1.337
C4H6O2 2,3-Butanedione 21 Bg 240 124 -116 1.936
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.232
COBr2 Carbonic dibromide 4 B1 757 504 -253 1.502
CBr2F2 Methane, dibromodifluoro- 3 A1 140 334 194 0.419
C6H5CN phenyl cyanide 19 B1 688 563 -125 1.222
C5H8 1,4-Pentadiene 31 B 721 580 -141 1.243
C5H8 1,4-Pentadiene 33 B 331 92 -239 3.617
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.234
C6H8 1,4-Cyclohexadiene 19 B1u 108 85 -23 1.277
C6H8 1,4-Cyclohexadiene 23 B2g 403 335 -68 1.203
LiOH lithium hydroxide 3 Π 257 394 137 0.651
CH3 Methyl radical 2 A2" 606 432 -175 1.405
BF3+ boron trifluoride cation 3 E' 1662 2081 420 0.798
CaF2 Calcium difluoride 2 A1 120 51 -69 2.338
N2O3 Dinitrogen trioxide 9 A" 63 138 75 0.457
SiH- silicon monohydride anion 1 Σ 2175 1686 -489 1.290
PO Phosphorus monoxide 1 Σ 1233 2487 1253 0.496
PN+ phosphorus nitride cation 1 Σ 1200 2283 1083 0.526