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/6-31G(2df,p)
Calculated values were scaled by 0.984.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 185 72 0.612
CH3COOH Acetic acid 18 A" 93 70 -23 1.338
CH3OH Methyl alcohol 12 A" 200 326 126 0.613
C2H6O2S Dimethyl sulfone 20 B1 262 202 -60 1.296
C2H4+ Ethylene cation 4 Au 84 -835 -920 -0.101
CH3COCl Acetyl Chloride 15 A" 166 134 -32 1.241
CBr2F2 Methane, dibromodifluoro- 3 A1 140 345 205 0.405
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.523
C3F8 perfluoropropane 13 A2 276 201 -75 1.372
CF2CCl2 difluorodichloroethylene 7 B1 1327 595 -732 2.230
CF2CCl2 difluorodichloroethylene 8 B1 989 310 -679 3.187
CF2CCl2 difluorodichloroethylene 11 B2 564 450 -114 1.253
CF2CCl2 difluorodichloroethylene 12 B2 323 171 -152 1.894
C3H6O 2-Propen-1-ol 22 A 377 301 -76 1.253
C3H6O 2-Propen-1-ol 24 A 188 118 -70 1.593
CH3OCHO methyl formate 18 A" 130 90 -40 1.449
C5H8 Cyclopentene 18 A' 254 160 -94 1.586
C4H4N2 Pyridazine 13 A2 421 338 -83 1.244
C2H2N4 sym-tetrazine 5 Au 335 268 -67 1.249
C2H2N4 sym-tetrazine 18 B3u 254 -60 -314 -4.215
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 532 181 0.660
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 336 -873 3.595
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 406 -127 1.313
C6F6 hexafluorobenzene 7 B2g 715 477 -238 1.500
C6F6 hexafluorobenzene 8 B2g 243 178 -65 1.363
C6F6 hexafluorobenzene 20 E2u 175 133 -42 1.314
C4H6O2 2,3-Butanedione 13 Au 1111 868 -243 1.280
C4H6O2 2,3-Butanedione 16 Au 48 -33 -81 -1.437
C4H6O2 2,3-Butanedione 21 Bg 240 51 -189 4.745
C6H4 Benzyne 24 B2 472 382 -90 1.236
C5H12 Propane, 2,2-dimethyl- 12 T1 203 318 115 0.638
C2H3NO3 Oxamic acid 3 A' 2600 3433 833 0.757
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 21 A" 162 87 -75 1.853
C3H6O Oxetane 12 A2 986 791 -195 1.247
C3H6O Oxetane 18 B1 90 -51 -140 -1.773
C3O2 Carbon suboxide 7 Πu 61 97 36 0.627
HCNO fulminic acid 5 Π 224 -206 -430 -1.088
Zn(CH3)2 dimethyl zinc 11 E' 134 103 -31 1.298
C5H8 1,4-Pentadiene 16 A 137 282 145 0.485
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 179 -48 1.269
CH3SSCH3 Disulfide, dimethyl 13 A 117 71 -46 1.638
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 134 -36 1.266
CuO Copper Monoxide 1 Σ 640 947 307 0.676
SiF2+ Silicon difluoride cation 2 A1 350 257 -93 1.363
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.325
CH3OO methylperoxy radical 12 A" 170 121 -49 1.407
CH3 Methyl radical 2 A2" 606 485 -122 1.251
CH2OH Hydroxymethyl radical 9 A 234 430 196 0.545
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 872 -264 1.303
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 165 -99 1.599
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 109 -249 3.291
CHCl2 dichloromethyl radical 4 A' 190 279 89 0.680
C4H6 Methylenecyclopropane 17 B1 360 290 -70 1.242
HClO4 perchloric acid 12 A" 191 138 -53 1.381
GaF3 Gallium trifluoride 4 E' 192 81 -111 2.383
AsF5 Arsenic pentafluoride 7 E' 123 98 -25 1.252
ZnCN Zinc monocyanide 3 Π 212 93 -119 2.281
PCl5 Phosphorus pentachloride 2 A1' 370 290 -80 1.276
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.223
N2O3 Dinitrogen trioxide 9 A" 63 153 90 0.411
Li2O dilithium oxide 3 Πu 112 163 52 0.683
C3 carbon trimer 3 Πu 63 108 45 0.585
B2Cl4 Diboron tetrachloride 9 E 104 80 -24 1.294
SF5Cl sulfur chloropentafluoride 5 B1 625 476 -149 1.312
SF5Cl sulfur chloropentafluoride 7 B2 505 317 -188 1.592
SF5Cl sulfur chloropentafluoride 11 E 397 251 -146 1.580
H3O+ hydronium cation 2 A1 954 728 -227 1.311
ZnH2 Zinc hydride 3 Πu 633 349 -284 1.813
C2H4O4 Formic acid dimer 2 Ag 2949 1936 -1013 1.523
C2H4O4 Formic acid dimer 13 Au 1050 81 -969 13.024
C2H4O4 Formic acid dimer 18 Bu 2939 2128 -810 1.381
C2H4O4 Formic acid dimer 24 Bu 268 478 210 0.561
ClOO chloroperoxy radical 3 A' 201 326 124 0.618
B2H6 Diborane 14 B2u 368 265 -103 1.388
H2OH2O water dimer 6 A' 311 540 229 0.576
H2OH2O water dimer 7 A' 143 300 157 0.476
H2OH2O water dimer 10 A" 523 768 245 0.681
H2OH2O water dimer 11 A" 108 185 77 0.584
H2OH2O water dimer 12 A" 88 -199 -287 -0.442
H2POH Phosphinous acid 9 A" 375 253 -123 1.486
Mg2 Magnesium diatomic 1 Σg 51 124 73 0.412
ZnCH3 Zinc monomethyl 6 E 315 563 248 0.559
ClONO chlorine nitrite 5 A' 270 195 -75 1.382
CH3BO Borane, methyloxo- 7 E 897 1356 459 0.661