return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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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/Def2TZVPP
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 301 101 0.664
C2Cl6 hexachloroethane 4 A1u 61 87 26 0.697
HCN+ hydrogen cyanide cation 3 Π 760 1195 435 0.636
CH2I2 Diiodomethane 3 A1 704 510 -194 1.379
CH2I2 Diiodomethane 4 A1 285 121 -164 2.351
CH2I2 Diiodomethane 7 B1 896 738 -158 1.215
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 198 -2762 14.971
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 255 -2705 11.624
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 679 -767 2.131
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 776 -668 1.861
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1505 779 0.483
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1511 881 0.417
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3128 2877 0.080
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3139 2937 0.064
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 112 -2898 26.927
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 770 -2240 3.910
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 994 -265 1.267
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3185 2422 0.240
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3210 3087 0.038
CHSNH2 thioformamide 12 A" 393 290 -103 1.357
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 709 -2370 4.342
H2CS- thioformaldehyde anion 4 B1 450 209 -241 2.155
CF2I2 difluorodiiodomethane 7 B1 200 287 87 0.697
CH2Cl chloromethyl radical 4 B1 402 136 -266 2.945
TeO2 Tellurium Dioxide 1 A1 823 294 -529 2.797
NF3 Nitrogen trifluoride 1 A1 1032 680 -352 1.518
NF3 Nitrogen trifluoride 2 A1 647 1083 436 0.597
NF3 Nitrogen trifluoride 3 E 907 518 -389 1.750
NF3 Nitrogen trifluoride 4 E 492 992 500 0.496
CaBr2 Calcium dibromide 3 Πu 72 41 -31 1.754
BCl3+ Boron Trichloride cation 3 E' 1104 742 -362 1.487
SiC2 Silicon dicarbide 3 B2 196 138 -58 1.419
C3 carbon trimer 3 Πu 63 48 -15 1.309
S3 Sulfur trimer 1 A1 581 268 -313 2.169
XeF4 Xenon tetrafluoride 5 B2u 216 178 -38 1.211
SiH2D2 silane-d2 6 B1 2183 1639 -544 1.332
SiH2D2 silane-d2 8 B2 1601 2268 667 0.706
NH4 Ammonium radical 1 A1 2552 2957 405 0.863
OPCl Phosphorus oxychloride 2 A' 308 513 205 0.600
OPCl Phosphorus oxychloride 3 A' 492 317 -175 1.550
CHFCl Chlorofluoromethyl radical 6 A 540 415 -125 1.303
H2CNCN cyanamide, methylene 3 A' 2208 3114 906 0.709
H2CNCN cyanamide, methylene 4 A' 1621 2313 692 0.701
SNO Nitrogen oxide sulfide 3 A' 792 510 -282 1.553
ONNO NO dimer 2 A1 239 402 162 0.596
ONNO NO dimer 3 A1 135 332 197 0.405
ONNO NO dimer 4 torsion A2 117 216 99 0.542
ONNO NO dimer 6 B2 429 755 326 0.568
INO Nitrosyl iodide 2 A' 216 525 309 0.411
INO Nitrosyl iodide 3 A' 470 248 -222 1.896