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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 QCISD(T)/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" 200 295 95 0.677
CH3CCH propyne 10 E 328 255 -73 1.284
CH2CCH2 allene 1 A1 3015 1067 -1948 2.826
CH2CCH2 allene 8 E 3086 1464 -1622 2.107
C3O2 Carbon suboxide 7 Πu 61 -111 -172 -0.551
CFCl2 dichlorofluoromethyl radical 2 A' 747 622 -125 1.202
C2H- Ethynyl anion 3 Π 505 410 -95 1.231
CH2Cl chloromethyl radical 4 B1 402 -119 -521 -3.383
NF3 Nitrogen trifluoride 1 A1 1032 620 -412 1.665
NF3 Nitrogen trifluoride 2 A1 647 999 352 0.647
NF3 Nitrogen trifluoride 3 E 907 472 -435 1.923
NF3 Nitrogen trifluoride 4 E 492 874 382 0.563
BCl3+ Boron Trichloride cation 3 E' 1104 641 -463 1.721
N2O4 Dinitrogen tetroxide 9 B2u 265 211 -54 1.256
SiC2 Silicon dicarbide 3 B2 196 -189 -385 -1.039
C4 Carbon tetramer 4 Πg 323 -252 -575 -1.283
C4 Carbon tetramer 5 Πu 160 -127 -287 -1.256
S3 Sulfur trimer 2 A1 281 546 265 0.515
SiH2D2 silane-d2 6 B1 2183 1612 -571 1.354
SiH2D2 silane-d2 8 B2 1601 2229 628 0.718
NH4 Ammonium radical 1 A1 2552 3002 450 0.850
GeF Germanium monofluoride 1 Σ 809 639 -171 1.267
BH3PH3 borane phosphine 12 E 447 368 -79 1.213
CHFCl Chlorofluoromethyl radical 6 A 540 398 -142 1.356
H2CNCN cyanamide, methylene 3 A' 2208 3077 869 0.718
H2CNCN cyanamide, methylene 4 A' 1621 2203 582 0.736
C2H3NO Nitrosoethylene 11 A' 490 340 -150 1.442
SNO Nitrogen oxide sulfide 1 A' 1527 500 -1027 3.052
ONNO NO dimer 3 A1 135 214 80 0.628
ONNO NO dimer 4 torsion A2 117 203 86 0.577