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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 CCSD(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" 200 296 96 0.676
CH3CCH propyne 10 E 328 256 -72 1.279
CH2CCH2 allene 1 A1 3015 1067 -1948 2.824
CH2CCH2 allene 8 E 3086 1465 -1621 2.107
C3O2 Carbon suboxide 7 Πu 61 -112 -173 -0.543
C2H- Ethynyl anion 3 Π 505 412 -93 1.225
CH2Cl chloromethyl radical 4 B1 402 -111 -513 -3.621
NF3 Nitrogen trifluoride 1 A1 1032 625 -407 1.652
NF3 Nitrogen trifluoride 2 A1 647 1007 360 0.643
NF3 Nitrogen trifluoride 3 E 907 475 -432 1.909
NF3 Nitrogen trifluoride 4 E 492 881 389 0.558
BCl3+ Boron Trichloride cation 3 E' 1104 660 -444 1.673
SiC2 Silicon dicarbide 3 B2 196 -196 -392 -1.001
C4 Carbon tetramer 4 Πg 323 -269 -592 -1.201
C4 Carbon tetramer 5 Πu 160 81 -79 1.966
S3 Sulfur trimer 2 A1 281 550 269 0.511
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 809 642 -167 1.261
BH3PH3 borane phosphine 12 E 447 368 -79 1.213
H2CNCN cyanamide, methylene 3 A' 2208 3078 870 0.717
H2CNCN cyanamide, methylene 4 A' 1621 2209 588 0.734
SNO Nitrogen oxide sulfide 1 A' 1527 501 -1027 3.051
ONNO NO dimer 3 A1 135 210 75 0.641
ONNO NO dimer 4 torsion A2 117 202 85 0.580
AlNC Aluminum isocyanide 3 Π 100 80 -20 1.255