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(T)/6-311G*
Calculated values were scaled by 0.9628.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 347 147 0.576
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.255
C2H2 Acetylene 4 Πg 612 326 -286 1.878
HCN+ hydrogen cyanide cation 3 Π 760 1712 952 0.444
CH3CCH propyne 9 E 633 497 -136 1.275
CH3CCH propyne 10 E 328 208 -120 1.575
CH2I2 Diiodomethane 3 A1 704 461 -243 1.526
CH2I2 Diiodomethane 4 A1 285 114 -171 2.501
CH2I2 Diiodomethane 7 B1 896 711 -185 1.260
CH2I2 Diiodomethane 9 B2 738 553 -185 1.335
CH3SCH3+ dimethyl sulfide cation 15 B1 172 83 -89 2.072
C2Br4 tetrabromoethene 4 Au 66 52 -14 1.277
C10H8 naphthalene 12 Au 581 410 -171 1.417
C10H8 naphthalene 27 B2g 770 402 -368 1.914
C10H8 naphthalene 28 B2g 461 -368 -829 -1.254
C6H5CHO benzaldehyde 32 A" 688 446 -242 1.542
C6H4Cl2 1,4-dichlorobenzene 16 B2g 687 398 -289 1.727
CH3CH2CH2CH3 Butane 5 Ag 1442 413 -1029 3.494
CH3CH2CH2CH3 Butane 8 Ag 1151 821 -330 1.401
CH3CH2CH2CH3 Butane 36 Bu 271 2976 2705 0.091
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 192 -2768 15.417
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 242 -2718 12.216
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 632 -814 2.287
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 738 -706 1.956
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1450 724 0.501
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1451 821 0.434
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 2980 2729 0.084
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 2988 2786 0.068
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 115 -2895 26.170
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 747 -2263 4.029
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 969 -290 1.299
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3037 2274 0.251
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3059 2936 0.040
CHSNH2 thioformamide 12 A" 393 45 -348 8.797
C3F6 hexafluoropropene 21 A" 60 34 -26 1.740
F2CCCF2 tetrafluoroallene 5 B2 2052 701 -1351 2.929
F2CCCF2 tetrafluoroallene 6 B2 1030 562 -468 1.834
F2CCCF2 tetrafluoroallene 7 B2 581 377 -204 1.540
CH2CCH2 allene 1 A1 3015 1032 -1983 2.920
CH2CCH2 allene 8 E 3086 1434 -1652 2.152
C3H6O Oxetane 18 B1 90 -38 -128 -2.379
C3O2 Carbon suboxide 7 Πu 61 -50 -111 -1.215
C6H4F2 1,4-difluorobenzene 16 B2g 692 555 -137 1.247
CBr4 Carbon tetrabromide 3 T2 672 257 -415 2.614
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 648 -2430 4.748
HCCBr bromoacetylene 4 Π 618 481 -137 1.285
HCCBr bromoacetylene 5 Π 295 165 -130 1.789
C6H6 Benzvalene 10 A1 996 731 -265 1.362
H2CS- thioformaldehyde anion 4 B1 450 -154 -604 -2.931
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 212 -125 1.588
LiOH lithium hydroxide 3 Π 257 395 139 0.649
NaOH sodium hydroxide 3 torsion Π 300 227 -73 1.324
CH3 Methyl radical 2 torsion A2" 606 428 -178 1.416
CH2OH Hydroxymethyl radical 8 torsion A 482 694 212 0.694
CH2OH Hydroxymethyl radical 9 torsion A 234 459 225 0.510
CHCl2 dichloromethyl radical 4 A' 190 301 111 0.631
CH2Cl chloromethyl radical 4 B1 402 -166 -568 -2.425
NF3 Nitrogen trifluoride 1 A1 1032 628 -404 1.644
NF3 Nitrogen trifluoride 2 A1 647 1003 356 0.645
NF3 Nitrogen trifluoride 3 E 907 478 -429 1.896
NF3 Nitrogen trifluoride 4 E 492 902 410 0.545
IF5 pentafluoroiodine 7 E 591 324 -267 1.823
CaBr2 Calcium dibromide 3 Πu 72 34 -38 2.115
CaF2 Calcium difluoride 2 A1 120 59 -61 2.024
OClO- Chlorine dioxide anion 1 A1 790 634 -156 1.247
OClO- Chlorine dioxide anion 2 A1 418 298 -120 1.403
BCl3+ Boron Trichloride cation 3 E' 1104 632 -472 1.748
Li2O dilithium oxide 3 Πu 112 56 -56 2.006
SiC2 Silicon dicarbide 3 B2 196 99 -97 1.976
C4 Carbon tetramer 4 Πg 323 219 -104 1.475
C4 Carbon tetramer 5 Πu 160 102 -58 1.562
S3 Sulfur trimer 2 A1 281 518 237 0.542
SeF4 Selenium tetrafluoride 4 A1 156 118 -38 1.324
SiH2D2 silane-d2 6 B1 2183 1546 -637 1.412
SiH2D2 silane-d2 8 B2 1601 2139 538 0.749
N(SiH3)3 trisilylamine 18 E' 190 979 789 0.194
BrO+ Bromine monoxide cation 1 Σ 840 660 -180 1.273
OPCl Phosphorus oxychloride 2 A' 308 462 154 0.667
OPCl Phosphorus oxychloride 3 A' 492 292 -200 1.684
H2OH2O water dimer 11 A" 108 167 59 0.646
Mg2 Magnesium diatomic 1 Σg 48 20 -27 2.338
Al2 Aluminum diatomic 1 Σg 284 421 137 0.674
CHFCl Chlorofluoromethyl radical 6 A 540 395 -145 1.367
H2CNCN cyanamide, methylene 3 A' 2208 2961 753 0.746
H2CNCN cyanamide, methylene 4 A' 1621 2153 532 0.753
C2H3NO Nitrosoethylene 11 A' 490 334 -156 1.466
SNO Nitrogen oxide sulfide 1 A' 1527 498 -1029 3.066
ONNO NO dimer 4 torsion A2 117 168 51 0.697