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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 MP4/daug-cc-pVTZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 286 86 0.699
C3O2 Carbon suboxide 7 Πu 61 -69 -130 -0.887
CO+ carbon monoxide cation 1 Σ 2184 2734 551 0.799
CFCl2 dichlorofluoromethyl radical 2 A' 747 619 -128 1.207
CH2NH+ Methanimine cation 4 A' 1370 1857 487 0.738
CN Cyano radical 1 Σ 2042 2716 674 0.752
C3H4 cyclopropene 4 A1 1483 1022 -461 1.451
C3H4 cyclopropene 5 A1 1110 777 -333 1.429
C3H4 cyclopropene 6 A1 905 -1685 -2590 -0.537
C3H4 cyclopropene 10 B1 1088 615 -473 1.769
C3H4 cyclopropene 11 B1 569 -1169 -1738 -0.487
C3H4 cyclopropene 15 B2 769 -551 -1320 -1.396
CH2Cl chloromethyl radical 4 B1 402 -141 -543 -2.850
HNC+ hydrogen isocyanide cation 2 Σ 2195 2689 494 0.816
HN3+ Hydrazoic acid cation 2 A' 1850 3011 1161 0.614
NO Nitric oxide 1 Σ 1876 3431 1555 0.547
NaO2 Sodium superoxide 1 A1 1094 1991 897 0.549
NaO2 Sodium superoxide 3 B2 333 1194 861 0.279
SiH2D2 silane-d2 6 B1 2183 1638 -545 1.333
SiH2D2 silane-d2 8 B2 1601 2264 663 0.707
NH4 Ammonium radical 1 A1 2552 3030 478 0.842
CHFCl Chlorofluoromethyl radical 6 A 540 405 -135 1.332
H2CNCN cyanamide, methylene 3 A' 2208 3079 871 0.717
H2CNCN cyanamide, methylene 4 A' 1621 2125 504 0.763
SNO Nitrogen oxide sulfide 3 A' 792 522 -270 1.516
ONNO NO dimer 1 A1 1868 1515 -354 1.233
ONNO NO dimer 4 torsion A2 117 219 102 0.533