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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 CCSD(T)/6-31+G**
Calculated values were scaled by 0.9596.

Species Name mode Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 383 -229 1.598
ClCN chlorocyanogen 3 Π 378 311 -67 1.215
CH3 Methyl radical 2 A2" 606 466 -140 1.301
AsH3+ Arsine cation 2 A1 452 671 219 0.674
NO2 Nitrogen dioxide 1 A1 1318 5250 3932 0.251
NO2 Nitrogen dioxide 2 A1 750 3598 2848 0.208
NO2 Nitrogen dioxide 3 B2 1618 4609 2991 0.351
CaOH Calcium monohydroxide 2 Σ 353 611 258 0.578
CaOH Calcium monohydroxide 3 Π 609 384 -225 1.584
PO Phosphorus monoxide 1 Σ 1233 1721 488 0.717
AlO Aluminum monoxide 1 Σ 979 16164 15185 0.061
H2OH2O water dimer 8 A' 103 161 58 0.638
H2OH2O water dimer 11 A" 108 159 51 0.680
H2OH2O water dimer 12 A" 88 135 47 0.653