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/3-21G
Calculated values were scaled by 0.907.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 335 251 0.251
CH3SH+ Methanethiol cation 8 A' 687 466 -221 1.475
C2H Ethynyl radical 3 Π 372 732 360 0.508
CH3 Methyl radical 2 A2" 606 170 -436 3.562
CH2OH Hydroxymethyl radical 8 A 482 784 302 0.615
CH2OH Hydroxymethyl radical 9 A 234 359 125 0.651
C2H3+ vinyl cation 2 A1 2217 2895 678 0.766
CCl carbon monochloride 1 Σ 877 572 -305 1.534
OClO Chlorine dioxide 1 A1 946 594 -351 1.591
OClO Chlorine dioxide 2 A1 448 268 -180 1.672
OClO Chlorine dioxide 3 B2 1110 825 -285 1.346
SF5 Sulfur pentafluoride 9 E 387 243 -145 1.596
MgOH magnesium hydroxide 3 Π 188 358 170 0.526
C4 Carbon tetramer 4 Πg 323 500 177 0.645
S3- Sulfur trimer anion 3 B2 594 -277 -871 -2.144
SiH- silicon monohydride anion 1 Σ 2175 1626 -549 1.337
SiCl Clorosilylidyne 1 Σ 536 392 -143 1.366
NBr nitrogen monobromide 1 Σ 692 70 -622 9.949
HS2 Thiosulfeno radical 3 A' 596 310 -286 1.924
SCl sulfur monochloride 1 Σ 577 431 -145 1.337
BrO Bromine monoxide 1 Σ 726 54 -672 13.502
ClOO chloroperoxy radical 1 A' 1443 986 -457 1.463
ClOO chloroperoxy radical 2 A' 414 703 289 0.589
ClOO chloroperoxy radical 3 A' 201 376 175 0.536
AsCl Arsenic monochloride 1 Σ 443 334 -109 1.325
AlP Aluminum monophosphide 1 Σ 457 316 -141 1.446
SF3 Sulfur trifluoride 5 A" 682 388 -294 1.759
ClS2 Sulfur chloride 1 A' 662 425 -237 1.558
HNB hydrogen nitrogen boron 3 Π 433 625 192 0.692
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.530
HSO3 HOSO2 3 A 1296 819 -477 1.582
HSO3 HOSO2 4 A 1097 778 -319 1.411