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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 QCISD(T)/6-31+G**
Calculated values were scaled by 0.939.

Species Name mode Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 368 -244 1.665
CH3 Methyl radical 2 A2" 606 456 -151 1.330
CH3 Methyl radical 2 A2" 606 456 -151 1.330
CH3 Methyl radical 2 A2" 606 456 -151 1.330
CH3 Methyl radical 2 A2" 606 456 -151 1.330
CuF Copper monofluoride 1 Σ 623 1220 597 0.510
CaOH Calcium monohydroxide 3 Π 609 400 -209 1.523
CaOH Calcium monohydroxide 2 Σ 353 547 194 0.646
O3 Ozone 3 B2 1042 840 -202 1.240
AsH3+ Arsine cation 2 A1 452 656 204 0.689
HClO4 perchloric acid 12 A" 191 155 -36 1.235
HClO4 perchloric acid 8 A' 405 334 -71 1.211
HClO4 perchloric acid 7 A' 548 451 -97 1.215