return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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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 B1B95/3-21G*
Calculated values were scaled by 0.9549.

Species Name mode Symmetry Experiment Theory difference ratio
CH3CONH2 Acetamide 20 A 259 391 132 0.662
CH3OH Methyl alcohol 12 A" 200 368 168 0.543
C2H4+ Ethylene cation 4 Au 84 -531 -615 -0.158
CHONH2 formamide 12 A" 289 498 209 0.580
HNCO Isocyanic acid 4 A' 777 572 -204 1.357
HNCO Isocyanic acid 5 A' 577 412 -165 1.401
CBr2F2 Methane, dibromodifluoro- 3 A1 140 327 187 0.429
C3F8 perfluoropropane 13 A2 276 194 -82 1.421
CF2CCl2 difluorodichloroethylene 7 B1 1327 636 -691 2.086
CF2CCl2 difluorodichloroethylene 8 B1 989 333 -656 2.974
CF2CCl2 difluorodichloroethylene 12 B2 323 170 -153 1.897
C3H6O 2-Propen-1-ol 22 A 377 293 -84 1.288
C3H6O 2-Propen-1-ol 24 A 188 100 -88 1.887
C2H2O2 Ethanedial 7 Au 127 194 67 0.654
C4H9N Pyrrolidine 36 A" 65 28 -37 2.317
C4H8O2 1,4-Dioxane 19 Au 288 219 -69 1.315
C5H8 Cyclopentene 18 A' 254 133 -121 1.916
N2H4 Hydrazine 6 A 780 594 -186 1.312
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 588 237 0.597
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 356 -853 3.395
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 383 -150 1.393
C6F6 hexafluorobenzene 8 B2g 243 186 -57 1.306
C6F6 hexafluorobenzene 20 E2u 175 135 -40 1.298
C4H6O2 2,3-Butanedione 21 Bg 240 105 -135 2.293
C2N2 Cyanogen 4 Πg 503 755 252 0.667
C5H12 Propane, 2,2-dimethyl- 12 T1 203 310 107 0.654
C2H3NO3 Oxamic acid 3 A' 2600 3369 769 0.772
C2H3NO3 Oxamic acid 15 A' 328 245 -83 1.336
C2H3NO3 Oxamic acid 21 A" 162 116 -46 1.397
C3H6O Oxetane 23 B2 1228 961 -267 1.278
C3O2 Carbon suboxide 7 Πu 61 145 84 0.421
HCNO fulminic acid 5 Π 224 527 303 0.425
C5H8 1,4-Pentadiene 16 A 137 298 161 0.460
C5H8 1,4-Pentadiene 17 A 102 80 -22 1.279
C4N2 2-Butynedinitrile 6 Πg 504 907 403 0.556
C4N2 2-Butynedinitrile 8 Πu 472 682 210 0.692
LiOH lithium hydroxide 3 Π 257 409 153 0.627
CuO Copper Monoxide 1 Σ 640 917 276 0.698
SiF2+ Silicon difluoride cation 2 A1 350 270 -80 1.296
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.689
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.328
FCO+ Carbonyl fluoride cation 3 Π 650 500 -150 1.301
C2H Ethynyl radical 3 Π 372 541 170 0.686
CH3 Methyl radical 2 A2" 606 464 -142 1.306
CH2OH Hydroxymethyl radical 9 A 234 424 190 0.552
ClCO carbonyl monochloride 3 A' 335 265 -70 1.263
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.317
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 145 -119 1.822
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 99 -259 3.598
OH- hydroxide anion 1 Σ 3738 2654 -1084 1.409
OH Hydroxyl radical 1 Σ 3738 3150 -588 1.187
NF2 Difluoroamino radical 2 A1 573 455 -118 1.261
C2Cl2 dichloroacetylene 4 Πg 333 496 163 0.671
HClO4 perchloric acid 12 A" 191 123 -68 1.552
HF Hydrogen fluoride 1 Σ 4138 3529 -610 1.173
NH3 Ammonia 2 A1 950 681 -269 1.396
H2O2 Hydrogen peroxide 4 A 371 77 -294 4.830
O2+ diatomic oxygen cation 1 Σg 1906 1431 -475 1.332
FOOF Perfluoroperoxide 1 A 1210 956 -254 1.266
FOOF Perfluoroperoxide 4 A 202 160 -42 1.260
FOOF Perfluoroperoxide 5 B 614 938 324 0.655
NF3 Nitrogen trifluoride 4 E 492 385 -107 1.276
BeF2 Beryllium fluoride 3 Πu 343 252 -91 1.360
BrF5 bromine pentafluoride 6 B2 281 209 -72 1.343
PCl5 Phosphorus pentachloride 2 A1' 370 263 -107 1.405
O3 Ozone 2 A1 705 553 -152 1.274
N2O4 Dinitrogen tetroxide 9 B2u 265 204 -61 1.299
N2O3 Dinitrogen trioxide 9 A" 63 157 94 0.401
Li2O dilithium oxide 3 Πu 112 71 -40 1.568
C3 carbon trimer 3 Πu 63 158 94 0.402
ND3 Ammonia-d3 2 A1 748 520 -228 1.438
NH2- amino anion 1 A1 3122 2578 -544 1.211
NH2- amino anion 3 B2 3190 2620 -571 1.218
SF5Cl sulfur chloropentafluoride 5 B1 625 456 -169 1.369
SF5Cl sulfur chloropentafluoride 7 B2 505 314 -191 1.610
SF5Cl sulfur chloropentafluoride 11 E 397 243 -154 1.635
H3O+ hydronium cation 2 A1 954 485 -470 1.970
C2H4O4 Formic acid dimer 2 Ag 2949 2184 -765 1.350
C2H4O4 Formic acid dimer 13 Au 1050 92 -958 11.406
C2H4O4 Formic acid dimer 24 Bu 268 403 135 0.665
ClOO chloroperoxy radical 1 A' 1443 1075 -368 1.343
H2OH2O water dimer 6 A' 311 527 216 0.590
H2OH2O water dimer 7 A' 143 277 134 0.516
H2OH2O water dimer 8 A' 103 202 99 0.510
H2OH2O water dimer 10 A" 523 852 329 0.614
H2OH2O water dimer 11 A" 108 218 110 0.496
H2POH Phosphinous acid 9 A" 375 223 -152 1.684
Mg2 Magnesium diatomic 1 Σg 51 97 46 0.528
ZnCH3 Zinc monomethyl 6 E 315 631 316 0.499
CH3BO Borane, methyloxo- 7 E 897 1454 557 0.617
ONONO Nitrosyl nitrite 9 B2 380 603 223 0.631