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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)=FULL/cc-pVQZ
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 0.675
HCN+ hydrogen cyanide cation 3 Π 760 2434 1674 0.312
CH2CCH2 allene 1 A1 3015 1090 -1925 2.767
CH2CCH2 allene 8 E 3086 1489 -1597 2.073
H2CS- thioformaldehyde anion 4 B1 450 255 -195 1.763
CaO Calcium monoxide 1 Σ 723 1805 1082 0.400
LiOH lithium hydroxide 3 Π 257 382 125 0.672
CH2OH Hydroxymethyl radical 9 torsion A 234 424 190 0.551
HCCN cyanomethylene 5 Π 129 -369 -498 -0.349
CH2Cl chloromethyl radical 4 B1 402 181 -221 2.218
NF3 Nitrogen trifluoride 1 A1 1032 663 -369 1.555
NF3 Nitrogen trifluoride 2 A1 647 1058 411 0.611
NF3 Nitrogen trifluoride 3 E 907 504 -403 1.800
NF3 Nitrogen trifluoride 4 E 492 941 449 0.523
AsSe Arsenic monoselenide 1 Σ 280 430 150 0.651
VO Vanadium monoxide 1 Σ 1002 1445 443 0.693
C4 Carbon tetramer 5 Πu 160 110 -50 1.455
S3 Sulfur trimer 2 A1 281 589 308 0.477
SiH2D2 silane-d2 6 B1 2183 1676 -507 1.303
SiH2D2 silane-d2 8 B2 1601 2319 718 0.690
NH4 Ammonium radical 1 A1 2552 2970 418 0.859
AlCN Aluminum monocyanide 3 Π 132 203 72 0.648
OPCl Phosphorus oxychloride 2 A' 308 510 202 0.604
OPCl Phosphorus oxychloride 3 A' 492 310 -182 1.585
H2OH2O water dimer 8 A' 103 148 45 0.695
H2OH2O water dimer 12 A" 88 127 39 0.695
Na2 Sodium diatomic 1 Σg 158 249 91 0.634
H2CNCN cyanamide, methylene 3 A' 2208 3104 896 0.711
H2CNCN cyanamide, methylene 4 A' 1621 2264 643 0.716
ONNO NO dimer 3 A1 135 248 113 0.543
ONNO NO dimer 4 torsion A2 117 221 104 0.530
ONNO NO dimer 6 B2 429 614 185 0.699
AlNC Aluminum isocyanide 3 Π 100 148 48 0.676