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 LSDA/cc-pVDZ
Calculated values were scaled by 0.989.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 183 70 0.618
CH3CONH2 Acetamide 20 A 259 192 -67 1.347
CH3COOH Acetic acid 18 A" 93 68 -25 1.377
CH3OH Methyl alcohol 12 A" 200 338 138 0.591
C2H6O2S Dimethyl sulfone 13 A2 326 259 -67 1.258
C2H6O2S Dimethyl sulfone 19 B1 396 317 -79 1.249
C2H6O2S Dimethyl sulfone 20 B1 262 196 -66 1.337
C2H4+ Ethylene cation 4 Au 84 -850 -934 -0.099
CHONH2 formamide 12 A" 289 237 -51 1.216
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.220
CBr2F2 Methane, dibromodifluoro- 3 A1 140 333 193 0.420
C2F6 hexafluoroethane 4 A1u 68 30 -38 2.269
C3F8 perfluoropropane 13 A2 276 201 -75 1.376
CF2CCl2 difluorodichloroethylene 7 B1 1327 580 -747 2.286
CF2CCl2 difluorodichloroethylene 8 B1 989 311 -678 3.180
CF2CCl2 difluorodichloroethylene 11 B2 564 447 -117 1.260
CF2CCl2 difluorodichloroethylene 12 B2 323 169 -154 1.911
C3H6O 2-Propen-1-ol 22 A 377 300 -78 1.259
C3H6O 2-Propen-1-ol 24 A 188 116 -72 1.615
CH3OCHO methyl formate 18 A" 130 80 -50 1.626
C5H8 Cyclopentene 18 A' 254 172 -82 1.475
C4H4N2 Pyridazine 13 A2 421 338 -83 1.245
C2H2N4 sym-tetrazine 5 Au 335 260 -75 1.288
C2H2N4 sym-tetrazine 18 B3u 254 43 -211 5.872
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 536 185 0.655
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 340 -869 3.560
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 409 -124 1.304
C6F6 hexafluorobenzene 8 B2g 243 182 -61 1.336
C6F6 hexafluorobenzene 20 E2u 175 132 -43 1.321
C4H6O2 2,3-Butanedione 13 Au 1111 865 -246 1.285
C4H6O2 2,3-Butanedione 16 Au 48 -44 -92 -1.085
C4H6O2 2,3-Butanedione 21 Bg 240 39 -201 6.176
C5H12 Propane, 2,2-dimethyl- 12 T1 203 316 113 0.643
C2H3NO3 Oxamic acid 3 A' 2600 3411 811 0.762
C2H3NO3 Oxamic acid 15 A' 328 253 -75 1.296
C2H3NO3 Oxamic acid 21 A" 162 91 -71 1.772
C3H6O Oxetane 12 A2 986 794 -192 1.242
C3H6O Oxetane 18 B1 90 -61 -151 -1.478
C3O2 Carbon suboxide 7 Πu 61 106 45 0.573
HCNO fulminic acid 5 Π 224 -144 -368 -1.560
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 180 -47 1.263
CH3ONO Methyl nitrite 15 A" 186 143 -43 1.299
CH3SSCH3 Disulfide, dimethyl 13 A 117 73 -44 1.593
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 137 -33 1.243
SiF2+ Silicon difluoride cation 2 A1 350 245 -105 1.427
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.674
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.325
CH3OO methylperoxy radical 12 A" 170 128 -42 1.331
CH3 Methyl radical 2 A2" 606 484 -122 1.252
CH2OH Hydroxymethyl radical 9 A 234 422 188 0.554
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 108 -250 3.304
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 169 -95 1.558
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 875 -261 1.298
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.644
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.273
HClO4 perchloric acid 12 A" 191 118 -73 1.619
ClFO3 Perchloryl fluoride 6 E 405 332 -73 1.221
PF5 Phosphorus pentafluoride 7 E' 174 139 -35 1.256
F2SO Thionyl Fluoride 4 A' 378 309 -69 1.223
HSO3F Fluorosulfonic acid 11 A 390 321 -69 1.215
BrF5 bromine pentafluoride 6 B2 281 198 -83 1.419
ClF3 Chlorine trifluoride 3 A1 328 262 -66 1.252
ClF3 Chlorine trifluoride 6 B2 442 359 -83 1.232
PCl5 Phosphorus pentachloride 2 A1' 370 285 -85 1.297
PCl5 Phosphorus pentachloride 7 E' 100 77 -23 1.293
N2O4 Dinitrogen tetroxide 9 B2u 265 215 -50 1.231
N2O3 Dinitrogen trioxide 9 A" 63 158 95 0.399
C3 carbon trimer 3 Πu 63 120 56 0.529
SF5 Sulfur pentafluoride 9 E 387 307 -81 1.263
SF5 Sulfur pentafluoride 3 A1 554 456 -98 1.214
B2Cl4 Diboron tetrachloride 9 E 104 81 -23 1.280
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
SF5Cl sulfur chloropentafluoride 5 B1 625 440 -185 1.419
SF5Cl sulfur chloropentafluoride 7 B2 505 303 -202 1.664
SF5Cl sulfur chloropentafluoride 11 E 397 239 -158 1.658
H3O+ hydronium cation 2 A1 954 786 -168 1.214
C2H4O4 Formic acid dimer 2 Ag 2949 1893 -1056 1.558
C2H4O4 Formic acid dimer 13 Au 1050 82 -968 12.823
C2H4O4 Formic acid dimer 18 Bu 2939 2051 -887 1.432
C2H4O4 Formic acid dimer 24 Bu 268 498 230 0.538
ClOO chloroperoxy radical 3 A' 201 320 118 0.630
B2H6 Diborane 13 B2u 950 782 -168 1.214
B2H6 Diborane 14 B2u 368 240 -128 1.531
H2OH2O water dimer 6 A' 311 644 333 0.483
H2OH2O water dimer 7 A' 143 351 208 0.407
H2OH2O water dimer 8 A' 103 195 92 0.528
H2OH2O water dimer 10 A" 523 812 289 0.644
H2OH2O water dimer 11 A" 108 229 121 0.472
H2OH2O water dimer 12 A" 88 -214 -302 -0.410
H2POH Phosphinous acid 9 A" 375 232 -143 1.618
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ClOF3 Chlorine trifluoride oxide 6 A' 224 184 -40 1.215
ClONO chlorine nitrite 5 A' 270 180 -90 1.500
CH3BO Borane, methyloxo- 7 E 897 1336 440 0.671
HSO3 HOSO2 3 A 1296 1027 -269 1.262