return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) 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

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 B3LYP/6-31G*
Calculated values were scaled by 0.9603.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.639
CH3CONH2 Acetamide 20 A 259 129 -130 2.006
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3COCH3 Acetone 12 A2 77 33 -44 2.306
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.273
C2H4+ Ethylene cation 4 Au 84 -419 -503 -0.201
CHONH2 formamide 12 A" 289 82 -206 3.511
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.265
CH3NO2 Methane, nitro- 11 A" 1583 3066 1483 0.516
CBr2F2 Methane, dibromodifluoro- 3 A1 140 312 172 0.448
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.511
C3F8 perfluoropropane 13 A2 276 210 -66 1.313
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.200
CF2CCl2 difluorodichloroethylene 7 B1 1327 567 -760 2.341
CF2CCl2 difluorodichloroethylene 8 B1 989 312 -677 3.175
CF2CCl2 difluorodichloroethylene 11 B2 564 438 -126 1.288
CF2CCl2 difluorodichloroethylene 12 B2 323 179 -144 1.805
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.669
C5H8 Cyclopentene 18 A' 254 134 -120 1.895
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 506 155 0.694
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 332 -877 3.642
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 396 -137 1.345
C6F6 hexafluorobenzene 7 B2g 715 501 -214 1.427
C6F6 hexafluorobenzene 8 B2g 243 176 -67 1.379
C6F6 hexafluorobenzene 20 E2u 175 131 -44 1.337
NH2CN cyanamide 5 A' 408 585 177 0.697
C4H6O2 2,3-Butanedione 21 Bg 240 109 -131 2.199
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.679
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.265
C2H3NO3 Oxamic acid 16 A" 984 785 -199 1.253
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.498
C3H6O Oxetane 18 B1 90 62 -27 1.438
C3O2 Carbon suboxide 7 Πu 61 124 63 0.491
C5H8 1,4-Pentadiene 16 A 137 288 151 0.475
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.390
SiF2+ Silicon difluoride cation 2 A1 350 279 -71 1.255
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.319
CH3OO methylperoxy radical 12 A" 170 134 -36 1.269
CH3 Methyl radical 2 A2" 606 435 -172 1.394
CH2OH Hydroxymethyl radical 9 A 234 433 199 0.541
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 865 -271 1.313
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 150 -114 1.757
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 100 -258 3.568
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.649
C4H6 Methylenecyclopropane 17 B1 360 282 -78 1.278
HClO4 perchloric acid 12 A" 191 151 -40 1.268
MgF2 Magnesium fluoride 3 Πu 165 132 -33 1.254
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.257
BrF5 bromine pentafluoride 6 B2 281 203 -78 1.385
ZnCN Zinc monocyanide 3 Π 212 49 -163 4.288
PCl5 Phosphorus pentachloride 2 A1' 370 257 -113 1.441
SF5 Sulfur pentafluoride 9 E 387 305 -82 1.268
C3 carbon trimer 3 Πu 63 178 114 0.357
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.587
CaOH Calcium monohydroxide 3 Π 609 329 -280 1.851
Cu2 Copper dimer 1 Σg 265 387 122 0.684
Fe(CO)5 Iron pentacarbonyl 5 A2' 383 300 -83 1.275
Fe(CO)5 Iron pentacarbonyl 13 E' 474 377 -98 1.259
Fe(CO)5 Iron pentacarbonyl 15 E' 74 33 -41 2.246
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.425
SF5Cl sulfur chloropentafluoride 7 B2 505 295 -210 1.712
SF5Cl sulfur chloropentafluoride 11 E 397 231 -166 1.720
ZnH2 Zinc hydride 3 Πu 633 499 -133 1.267
C2H4O4 Formic acid dimer 13 Au 1050 72 -978 14.514
ClOO chloroperoxy radical 2 A' 414 300 -114 1.378
ClOO chloroperoxy radical 3 A' 201 122 -80 1.657
H2OH2O water dimer 6 A' 311 445 134 0.698
H2OH2O water dimer 7 A' 143 224 81 0.639
H2OH2O water dimer 11 A" 108 164 56 0.659
H2OH2O water dimer 12 A" 88 -65 -153 -1.348
H2POH Phosphinous acid 9 A" 375 241 -134 1.556
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.531
CH3BO Borane, methyloxo- 7 E 897 1432 535 0.626