return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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/6-31+G**
Calculated values were scaled by 0.9338.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 297 97 0.674
C2H2 Acetylene 4 Πg 612 444 -168 1.377
CH3CCH propyne 10 E 328 250 -78 1.313
CH3SCH3+ dimethyl sulfide cation 15 B1 172 130 -42 1.328
C2Br4 tetrabromoethene 7 B2g 464 932 468 0.498
C6H5CHO benzaldehyde 32 A" 688 432 -256 1.594
CH2BrCH2Br Ethane, 1,2-dibromo- 10 A 91 69 -22 1.311
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 183 -2777 16.194
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 240 -2720 12.357
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 627 -819 2.305
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 736 -708 1.962
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1435 709 0.506
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1437 807 0.438
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 2963 2712 0.085
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 2972 2770 0.068
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 131 -2879 23.056
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 738 -2272 4.077
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 956 -303 1.317
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3022 2259 0.252
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3045 2922 0.040
CHSNH2 thioformamide 12 A" 393 218 -175 1.805
C3F6 hexafluoropropene 21 A" 60 33 -27 1.842
CH2CClCHCH2 1,3-Butadiene, 2-chloro- 24 A" 144 100 -44 1.444
C3O2 Carbon suboxide 7 Πu 61 117 56 0.522
H2CS- thioformaldehyde anion 4 B1 450 238 -212 1.889
CH2ClCCCl 1,3-dichloropropyne 9 A' 282 214 -68 1.319
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 162 -175 2.081
CH3 Methyl radical 2 torsion A2" 606 454 -152 1.335
CH2Cl chloromethyl radical 4 B1 402 -39 -441 -10.313
NF3 Nitrogen trifluoride 1 A1 1032 609 -423 1.693
NF3 Nitrogen trifluoride 2 A1 647 989 342 0.654
NF3 Nitrogen trifluoride 3 E 907 462 -445 1.965
NF3 Nitrogen trifluoride 4 E 492 904 412 0.544
OClO- Chlorine dioxide anion 2 A1 418 324 -94 1.292
BCl3+ Boron Trichloride cation 3 E' 1104 747 -356 1.477
N2O4 Dinitrogen tetroxide 4 torsion Au 82 62 -20 1.331
SiC2 Silicon dicarbide 3 B2 196 -142 -338 -1.383
C3 carbon trimer 3 Πu 63 -101 -164 -0.628
C4 Carbon tetramer 4 Πg 323 220 -103 1.470
S3 Sulfur trimer 2 A1 281 557 276 0.505
SiH2D2 silane-d2 6 B1 2183 1563 -620 1.397
SiH2D2 silane-d2 8 B2 1601 2163 562 0.740
OPCl Phosphorus oxychloride 2 A' 308 477 169 0.645
OPCl Phosphorus oxychloride 3 A' 492 294 -198 1.671
CHFCl Chlorofluoromethyl radical 6 A 540 383 -157 1.410
H2CNCN cyanamide, methylene 3 A' 2208 2961 753 0.746
H2CNCN cyanamide, methylene 4 A' 1621 2164 543 0.749
SNO Nitrogen oxide sulfide 1 A' 1527 485 -1043 3.151
ONNO NO dimer 3 A1 135 296 161 0.455
ONNO NO dimer 4 torsion A2 117 188 71 0.621
ONNO NO dimer 6 B2 429 669 240 0.641
AlNC Aluminum isocyanide 3 Π 100 155 55 0.645