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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=FULL/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" 200 297 97 0.674
CH3CCH propyne 10 E 328 257 -71 1.277
C3O2 Carbon suboxide 7 Πu 61 -75 -136 -0.819
CO+ carbon monoxide cation 1 Σ 2184 2712 528 0.805
CH3Li methyl lithium 6 E 409 100 -309 4.086
CFCl2 dichlorofluoromethyl radical 2 A' 747 622 -125 1.201
CH2NH+ Methanimine cation 4 A' 1370 1855 485 0.738
CN Cyano radical 1 Σ 2042 2653 611 0.770
C2H- Ethynyl anion 3 Π 505 418 -87 1.209
CH2Cl chloromethyl radical 4 B1 402 -119 -521 -3.369
HNC+ hydrogen isocyanide cation 2 Σ 2195 2654 458 0.827
HN3+ Hydrazoic acid cation 2 A' 1850 3072 1222 0.602
HOCl+ hypochlorous acid cation 3 A' 830 1329 499 0.624
NO Nitric oxide 1 Σ 1876 3602 1726 0.521
NaO2 Sodium superoxide 3 B2 333 971 638 0.343
C4 Carbon tetramer 4 Πg 323 -199 -522 -1.627
C4 Carbon tetramer 5 Πu 160 125 -35 1.280
S3 Sulfur trimer 2 A1 281 543 262 0.518
SiH2D2 silane-d2 6 B1 2183 1636 -547 1.334
SiH2D2 silane-d2 8 B2 1601 2262 661 0.708
NH4 Ammonium radical 1 A1 2552 3003 451 0.850
BH3PH3 borane phosphine 12 E 447 370 -77 1.208
CHFCl Chlorofluoromethyl radical 6 A 540 398 -142 1.356
H2CNCN cyanamide, methylene 3 A' 2208 3082 874 0.716
H2CNCN cyanamide, methylene 4 A' 1621 2111 490 0.768
SNO Nitrogen oxide sulfide 3 A' 792 520 -273 1.525