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 CCSD/6-311G*
Calculated values were scaled by 0.9535.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 343 143 0.583
C2Cl6 hexachloroethane 4 A1u 61 90 29 0.678
C2H2 Acetylene 4 Πg 612 410 -202 1.493
CH3CCH propyne 10 E 328 256 -72 1.281
CH2I2 Diiodomethane 3 A1 704 468 -236 1.504
CH2I2 Diiodomethane 4 A1 285 116 -169 2.465
CH2I2 Diiodomethane 9 B2 738 568 -170 1.299
CH3SCH3+ dimethyl sulfide cation 15 B1 172 130 -42 1.322
C6H5CHO benzaldehyde 32 A" 688 509 -179 1.352
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 192 -2768 15.386
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 244 -2716 12.144
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 641 -805 2.254
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 749 -695 1.928
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1448 722 0.501
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1449 819 0.435
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 2972 2721 0.084
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 2979 2777 0.068
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 114 -2896 26.453
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 746 -2264 4.033
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 971 -288 1.297
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3028 2265 0.252
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3049 2926 0.040
CHSNH2 thioformamide 12 A" 393 152 -241 2.592
C3F6 hexafluoropropene 21 A" 60 37 -23 1.640
C3O2 Carbon suboxide 7 Πu 61 -58 -119 -1.060
H2CS- thioformaldehyde anion 4 B1 450 -102 -552 -4.424
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 249 -88 1.353
LiOH lithium hydroxide 3 Π 257 389 132 0.659
NaOH sodium hydroxide 3 torsion Π 300 215 -85 1.394
CH3 Methyl radical 2 torsion A2" 606 428 -179 1.417
CH2OH Hydroxymethyl radical 9 torsion A 234 447 213 0.524
CH2Cl chloromethyl radical 4 B1 402 -146 -548 -2.760
NF3 Nitrogen trifluoride 1 A1 1032 650 -382 1.588
NF3 Nitrogen trifluoride 2 A1 647 1038 391 0.623
NF3 Nitrogen trifluoride 3 E 907 495 -412 1.831
NF3 Nitrogen trifluoride 4 E 492 961 469 0.512
CaBr2 Calcium dibromide 3 Πu 72 35 -37 2.078
OClO- Chlorine dioxide anion 2 A1 418 318 -100 1.314
BCl3+ Boron Trichloride cation 3 E' 1104 758 -346 1.456
SiC2 Silicon dicarbide 3 B2 196 -65 -261 -3.026
S3 Sulfur trimer 2 A1 281 553 272 0.508
NI3 Nitrogen triiodide 3 E 354 520 166 0.681
SiHF3 trifluorosilane 6 E 306 828 522 0.369
SiH2D2 silane-d2 6 B1 2183 1537 -646 1.420
SiH2D2 silane-d2 8 B2 1601 2126 525 0.753
Br3- tribromide anion 2 Σu 214 163 -51 1.316
OPCl Phosphorus oxychloride 2 A' 308 473 165 0.652
OPCl Phosphorus oxychloride 3 A' 492 301 -191 1.633
Mg2 Magnesium diatomic 1 Σg 48 15 -33 3.271
Al2 Aluminum diatomic 1 Σg 284 444 160 0.640
CHFCl Chlorofluoromethyl radical 6 A 540 397 -143 1.360
H2CNCN cyanamide, methylene 3 A' 2208 2959 751 0.746
H2CNCN cyanamide, methylene 4 A' 1621 2212 591 0.733
SNO Nitrogen oxide sulfide 1 A' 1527 502 -1025 3.044
ONNO NO dimer 3 A1 135 312 177 0.432
ONNO NO dimer 4 torsion A2 117 220 103 0.533
ONNO NO dimer 6 B2 429 684 255 0.627