return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

19 02 11 15 45

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 MP2/daug-cc-pVDZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 298 98 0.672
C2H2 Acetylene 4 Πg 612 432 -180 1.417
CH3CCH propyne 10 E 328 267 -61 1.230
C8H8 cubane 12 T1u 853 3147 2294 0.271
C8H8 cubane 15 T2g 821 3133 2312 0.262
C8H8 cubane 16 T2g 665 1170 505 0.568
C3O2 Carbon suboxide 7 Πu 61 -77 -138 -0.796
HCNO fulminic acid 5 torsion Π 224 -364 -588 -0.616
CO+ carbon monoxide cation 1 Σ 2184 2855 671 0.765
CH2NH+ Methanimine cation 4 A' 1370 1890 520 0.725
CN Cyano radical 1 Σ 2042 2835 793 0.720
CH2Cl chloromethyl radical 4 B1 402 -184 -586 -2.188
HNC+ hydrogen isocyanide cation 2 Σ 2195 2792 597 0.786
HN3+ Hydrazoic acid cation 2 A' 1850 3326 1476 0.556
SF4 Sulfur tetrafluoride 3 A1 532 855 323 0.622
SF4 Sulfur tetrafluoride 4 A1 228 558 330 0.409
SF4 Sulfur tetrafluoride 7 B1 353 837 484 0.422
SF4 Sulfur tetrafluoride 9 B2 475 756 281 0.628
HOCl+ hypochlorous acid cation 3 A' 830 1301 471 0.638
NO Nitric oxide 1 Σ 1876 3660 1784 0.513
NO2 Nitrogen dioxide 3 B2 1618 2513 895 0.644
BCl3+ Boron Trichloride cation 3 E' 1104 1536 432 0.719
GaO Gallium monoxide 1 Σ 755 589 -166 1.282
NaO2 Sodium superoxide 3 B2 333 1339 1006 0.249
SiC2 Silicon dicarbide 3 B2 196 -169 -366 -1.160
LiO2 Lithium dioxide 3 B2 509 1355 846 0.376
C4 Carbon tetramer 4 Πg 323 -165 -488 -1.961
C4 Carbon tetramer 5 Πu 160 129 -31 1.239
SiH2D2 silane-d2 6 B1 2183 1643 -540 1.328
SiH2D2 silane-d2 8 B2 1601 2274 673 0.704
NH4 Ammonium radical 1 A1 2552 3018 466 0.846
GeF Germanium monofluoride 1 Σ 809 643 -166 1.258
BrO+ Bromine monoxide cation 1 Σ 840 1251 411 0.671
CHFCl Chlorofluoromethyl radical 6 A 540 406 -134 1.329
H2CNCN cyanamide, methylene 3 A' 2208 3119 911 0.708
H2CNCN cyanamide, methylene 4 A' 1621 2139 518 0.758
ONNO NO dimer 2 A1 239 346 107 0.692
ONNO NO dimer 3 A1 135 318 183 0.423
ONNO NO dimer 4 torsion A2 117 281 164 0.416
ONNO NO dimer 6 B2 429 613 184 0.700