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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/cc-pVDZ
Calculated values were scaled by 0.9567.

Species Name mode Symmetry Experiment Theory difference ratio
HCN+ hydrogen cyanide cation 2 Σ 1800 2717 917 0.662
C6H4O2 parabenzoquinone 30 B3u 109 88 -21 1.236
C5H8 Cyclopentene 18 A' 254 172 -82 1.479
CH2NN diazomethane 6 B1 406 290 -116 1.402
NH2CN cyanamide 5 A' 408 730 322 0.559
COBr2 Carbonic dibromide 6 B2 512 345 -167 1.484
C2H5 Ethyl radical 9 A' 528 428 -100 1.234
CN Cyano radical 1 Σ 2069 2529 460 0.818
C2H Ethynyl radical 3 Π 372 728 356 0.511
OH- hydroxide anion 1 Σ 3738 3326 -412 1.124
AsH3+ Arsine cation 2 A1 452 677 225 0.668
BrF5 bromine pentafluoride 6 B2 281 232 -49 1.213
C3 carbon trimer 3 Πu 63 130 66 0.489
ClOO chloroperoxy radical 2 A' 414 1031 617 0.401
ClOO chloroperoxy radical 3 A' 201 485 284 0.415
H2OH2O water dimer 11 A" 108 162 54 0.668
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.597
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3NH2 methyl amine 14 A" 1195 945 -250 1.264
HCN+ hydrogen cyanide cation 1 Σ 3050 3519 469 0.867
C4H6O2 2,3-Butanedione 21 Bg 240 126 -114 1.910
COBr2 Carbonic dibromide 4 B1 757 506 -251 1.497
C2Cl2+ dichloroacetylene cation 5 Πu 233 183 -50 1.275
NO Nitric oxide 1 Σ 1904 2917 1013 0.653
CH3 Methyl radical 2 A2" 606 382 -225 1.588
CH2OH Hydroxymethyl radical 9 A 234 427 193 0.548
O3 Ozone 3 B2 1042 1650 608 0.632
N2O3 Dinitrogen trioxide 9 A" 63 146 83 0.432
MgOH magnesium hydroxide 3 Π 188 129 -59 1.459
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.248
PN+ phosphorus nitride cation 1 Σ 1200 1966 766 0.610
CBr2F2 Methane, dibromodifluoro- 3 A1 140 332 192 0.422
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.266