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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/6-31+G**
Calculated values were scaled by 0.9423.

Species Name mode Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 471 -141 1.298
HCN+ hydrogen cyanide cation 2 Σ 1800 2708 908 0.665
CH3COOCH3 methyl acetate 27 A" 110 57 -53 1.942
C6H4O2 parabenzoquinone 16 B2g 794 571 -223 1.391
C6H4O2 parabenzoquinone 30 B3u 109 75 -33 1.446
C3H2N2 Malononitrile 6 A1 167 136 -31 1.224
C4H8O Furan, tetrahydro- 33 B 137 57 -80 2.404
C5H8 Cyclopentene 18 A' 254 163 -91 1.558
CH2NN diazomethane 6 B1 406 321 -85 1.264
NH2CN cyanamide 5 A' 408 633 225 0.645
C6H5F Fluorobenzene 18 B1 685 479 -206 1.429
C6H4F2 1,4-difluorobenzene 16 B2g 692 460 -232 1.503
C5H8 1,4-Pentadiene 16 A 137 284 147 0.483
COBr2 Carbonic dibromide 6 B2 512 344 -168 1.488
CaO Calcium monoxide 1 Σ 732 559 -173 1.309
C6H5O phenoxy radical 19 B1 472 390 -82 1.211
C2Cl2+ dichloroacetylene cation 4 Πg 318 232 -86 1.372
AsH3+ Arsine cation 2 A1 452 665 213 0.680
Li2O dilithium oxide 3 Πu 112 84 -28 1.330
CaOH Calcium monohydroxide 2 Σ 353 554 201 0.637
CaOH Calcium monohydroxide 3 Π 609 415 -194 1.467
ZnCH3 Zinc monomethyl 6 E 315 599 284 0.526
CH3NH2 methyl amine 14 A" 1195 934 -261 1.280
HCN+ hydrogen cyanide cation 1 Σ 3050 3496 446 0.872
C6H4O2 parabenzoquinone 17 B2g 241 94 -147 2.569
C4H6O2 2,3-Butanedione 9 Ag 614 511 -103 1.201
C4H6O2 2,3-Butanedione 16 Au 48 40 -8 1.204
C4H6O2 2,3-Butanedione 21 Bg 240 111 -129 2.158
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.221
COBr2 Carbonic dibromide 4 B1 757 508 -249 1.491
C2Cl2+ dichloroacetylene cation 5 Πu 233 167 -66 1.392
ClONO2 Chlorine nitrate 9 A" 124 102 -21 1.208
N2O3 Dinitrogen trioxide 9 A" 63 122 59 0.517
SiH- silicon monohydride anion 1 Σ 2175 1801 -374 1.208
PN+ phosphorus nitride cation 1 Σ 1200 2110 910 0.569
CBr2F2 Methane, dibromodifluoro- 3 A1 140 327 187 0.428
NH2CN cyanamide 9 A" 435 359 -76 1.213
C5H8 1,4-Pentadiene 31 B 721 575 -146 1.253
C5H8 1,4-Pentadiene 33 B 331 91 -240 3.632
C6H8 1,4-Cyclohexadiene 19 B1u 108 75 -33 1.450
C6H8 1,4-Cyclohexadiene 23 B2g 403 291 -112 1.383
CH3 Methyl radical 2 A2" 606 454 -152 1.335