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 BLYP/cc-pVTZ
Calculated values were scaled by 0.997.

Species Name mode Symmetry Experiment Theory difference ratio
CH3CONH2 Acetamide 20 A 259 121 -138 2.138
CH3COOH Acetic acid 18 A" 93 68 -25 1.368
CH3OH Methyl alcohol 12 A" 200 297 97 0.673
CH3COCH3 Acetone 12 A2 77 12 -65 6.541
C2H4+ Ethylene cation 4 Au 84 -612 -696 -0.137
CHONH2 formamide 12 A" 289 178 -111 1.626
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 227 -49 1.216
CH3COCl Acetyl Chloride 15 A" 166 124 -42 1.339
CBr2F2 Methane, dibromodifluoro- 3 A1 140 302 162 0.464
C3F8 perfluoropropane 13 A2 276 216 -60 1.280
CH3COOCH3 methyl acetate 27 A" 110 10 -100 11.200
CF2CCl2 difluorodichloroethylene 7 B1 1327 549 -778 2.417
CF2CCl2 difluorodichloroethylene 8 B1 989 309 -680 3.196
CF2CCl2 difluorodichloroethylene 11 B2 564 432 -132 1.306
CF2CCl2 difluorodichloroethylene 12 B2 323 180 -143 1.790
C3H6O 2-Propen-1-ol 23 A 277 222 -55 1.247
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.693
CH3OCHO methyl formate 18 A" 130 103 -27 1.268
C4H8O Furan, tetrahydro- 17 A 286 237 -49 1.206
C4H8O2 1,4-Dioxane 19 Au 288 236 -52 1.220
C5H8 Cyclopentene 18 A' 254 122 -132 2.089
C2H2N4 sym-tetrazine 18 B3u 254 165 -89 1.543
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 514 163 0.683
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 326 -883 3.707
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 395 -138 1.350
C6F6 hexafluorobenzene 8 B2g 243 177 -66 1.375
C6F6 hexafluorobenzene 20 E2u 175 130 -45 1.351
C4H6O2 2,3-Butanedione 9 Ag 614 493 -121 1.245
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.225
Cl2CS Thiophosgene 5 B2 816 674 -142 1.210
C2H3NO3 Oxamic acid 3 A' 2600 3470 870 0.749
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.267
C2H3NO3 Oxamic acid 16 A" 984 792 -192 1.242
C2H3NO3 Oxamic acid 17 A" 815 655 -160 1.244
C2H3NO3 Oxamic acid 18 A" 745 615 -130 1.211
C2H3NO3 Oxamic acid 21 A" 162 61 -101 2.642
C3H6O Oxetane 12 A2 986 818 -168 1.205
C3H6O Oxetane 18 B1 90 51 -39 1.769
C3H6O Oxetane 23 B2 1228 953 -275 1.288
HCNO fulminic acid 5 Π 224 -229 -453 -0.980
CBr4 Carbon tetrabromide 3 T2 672 554 -118 1.213
C5H8 1,4-Pentadiene 16 A 137 295 158 0.464
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.214
CH3ONO Methyl nitrite 9 A' 627 479 -148 1.309
CH3ONO Methyl nitrite 15 A" 186 126 -60 1.472
C2F2 difluoroacetylene 4 Πg 270 188 -82 1.434
C4H6O Cyclobutanone 12 A2 1163 913 -250 1.274
C4H6O Cyclobutanone 13 A2 909 605 -304 1.503
C4H6O Cyclobutanone 20 B1 63 26 -37 2.394
SiF2+ Silicon difluoride cation 2 A1 350 264 -86 1.325
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.690
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 351 -105 1.301
CH3OO methylperoxy radical 12 A" 170 122 -48 1.395
CH2OH Hydroxymethyl radical 9 A 234 421 187 0.555
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 870 -266 1.305
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 153 -111 1.720
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 103 -255 3.475
C3H3 Propargyl radical 7 B1 490 404 -86 1.213
CH3CO Acetyl radical 4 A' 1420 3017 1597 0.471
CHCl2 dichloromethyl radical 4 A' 190 288 98 0.659
C4H6 Methylenecyclopropane 17 B1 360 276 -84 1.304
HClO4 perchloric acid 7 A' 548 448 -100 1.223
HClO4 perchloric acid 12 A" 191 146 -45 1.312
SOCl2 thionyl chloride 4 A' 194 154 -40 1.260
F2SO Thionyl Fluoride 4 A' 378 308 -70 1.225
BrF3 Bromine trifluoride 3 A1 242 188 -54 1.286
BrF5 bromine pentafluoride 3 A1 369 296 -73 1.248
BrF5 bromine pentafluoride 6 B2 281 186 -95 1.514
BrF5 bromine pentafluoride 8 E 415 344 -71 1.207
ClF3 Chlorine trifluoride 3 A1 328 242 -86 1.357
ClF3 Chlorine trifluoride 6 B2 442 348 -94 1.272
Cl2O Dichlorine monoxide 3 B2 686 530 -156 1.294
S2Cl2 Disulfur dichloride 5 B 461 373 -88 1.235
NCl3 nitrogen trichloride 3 E 642 494 -148 1.298
PCl5 Phosphorus pentachloride 2 A1' 370 248 -122 1.492
PCl5 Phosphorus pentachloride 7 E' 100 78 -22 1.287
S8 Octasulfur 3 B1 411 286 -125 1.439
S8 Octasulfur 10 E3 437 334 -103 1.308
N2O4 Dinitrogen tetroxide 9 B2u 265 180 -85 1.470
N2O3 Dinitrogen trioxide 9 A" 63 131 68 0.481
SF5 Sulfur pentafluoride 3 A1 554 441 -113 1.257
SF5 Sulfur pentafluoride 8 E 525 433 -92 1.213
SF5 Sulfur pentafluoride 9 E 387 301 -86 1.284
S3- Sulfur trimer anion 3 B2 594 493 -101 1.204
SiH- silicon monohydride anion 1 Σ 2175 1716 -459 1.267
SF5Cl sulfur chloropentafluoride 4 A1 402 330 -72 1.217
SF5Cl sulfur chloropentafluoride 5 B1 625 440 -185 1.419
SF5Cl sulfur chloropentafluoride 7 B2 505 293 -212 1.725
SF5Cl sulfur chloropentafluoride 11 E 397 232 -165 1.714
C2H4O4 Formic acid dimer 13 Au 1050 74 -976 14.158
ClONO2 Chlorine nitrate 7 A' 273 210 -63 1.303
Cl3- trichloride anion 2 Σu 327 262 -65 1.248
BrOBr Bromine oxide 3 B2 629 506 -123 1.244
H2OH2O water dimer 8 A' 103 154 51 0.670
H2OH2O water dimer 11 A" 108 172 64 0.629
H2OH2O water dimer 12 A" 88 63 -25 1.390
H2POH Phosphinous acid 9 A" 375 242 -133 1.551
ClOF3 Chlorine trifluoride oxide 4 A' 482 390 -92 1.237
ClOF3 Chlorine trifluoride oxide 5 A' 319 247 -72 1.293
ClOF3 Chlorine trifluoride oxide 6 A' 224 179 -45 1.254
ClOF3 Chlorine trifluoride oxide 9 A" 412 316 -96 1.302
ClS2 Sulfur chloride 2 A' 450 372 -78 1.211
BrONO2 Bromine nitrate 5 A' 564 454 -110 1.242
ClONO chlorine nitrite 4 A' 406 268 -138 1.517
ClONO chlorine nitrite 5 A' 270 148 -122 1.824
CH3BO Borane, methyloxo- 7 E 897 1422 525 0.631
HSO3 HOSO2 3 A 1296 1062 -234 1.221