return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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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 ROHF/6-311G*
Calculated values were scaled by 0.8556.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 408 324 0.206
C2H Ethynyl radical 3 Π 372 627 255 0.593
CH2OH Hydroxymethyl radical 8 A 482 811 329 0.594
CH2OH Hydroxymethyl radical 9 A 234 371 137 0.630
C2H3+ vinyl cation 2 A1 2217 2753 536 0.805
CHCl2 dichloromethyl radical 4 A' 190 278 88 0.684
ZnCl Zinc monochloride 1 Σ 391 266 -124 1.467
S3- Sulfur trimer anion 3 B2 594 384 -210 1.547
ZnH Zinc monohydride 1 Σ 1608 988 -620 1.627
AlO Aluminum monoxide 1 Σ 979 680 -299 1.440
ClOO chloroperoxy radical 2 A' 414 662 248 0.625
ClOO chloroperoxy radical 3 A' 201 410 208 0.491
ZnCH3 Zinc monomethyl 6 E 315 559 244 0.563
HSO3 HOSO2 4 A 1097 780 -317 1.407