return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) 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/6-31+G**
Calculated values were scaled by 0.9839.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 313 113 0.639
C3H6O 2-Propen-1-ol 24 A 188 117 -72 1.614
NH2CN cyanamide 6 A' 487 348 -139 1.398
C4H6O2 2,3-Butanedione 13 Au 1111 875 -236 1.270
C4H6O2 2,3-Butanedione 16 Au 48 36 -12 1.352
C4H6O2 2,3-Butanedione 21 Bg 240 76 -164 3.151
C5H12 Propane, 2,2-dimethyl- 12 T1 203 325 122 0.626
C2H3NO3 Oxamic acid 3 A' 2600 3424 824 0.759
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.281
C2H3NO3 Oxamic acid 16 A" 984 793 -191 1.241
C2H3NO3 Oxamic acid 21 A" 162 80 -82 2.013
C3H6O Oxetane 12 A2 986 798 -188 1.236
C3H6O Oxetane 18 B1 90 -82 -171 -1.099
C3O2 Carbon suboxide 7 Πu 61 174 113 0.350
HCNO fulminic acid 5 Π 224 169 -55 1.328
C5H8 1,4-Pentadiene 16 A 137 287 150 0.478
HCCBr bromoacetylene 5 Π 295 459 164 0.642
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.245
CH3SSCH3 Disulfide, dimethyl 13 A 117 83 -34 1.402
C6H6 Benzvalene 10 A1 996 741 -255 1.345
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 136 -34 1.245
H2CS- thioformaldehyde anion 4 B1 450 354 -96 1.270
SiF2+ Silicon difluoride cation 2 A1 350 260 -90 1.345
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.337
CH3OO methylperoxy radical 12 A" 170 129 -41 1.321
CH2OH Hydroxymethyl radical 9 A 234 361 127 0.648
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 875 -261 1.299
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 159 -105 1.656
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 107 -251 3.350
HCCN cyanomethylene 5 Π 129 -142 -271 -0.905
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.274
C2Cl2 dichloroacetylene 4 Πg 333 232 -101 1.437
ClFO3 Perchloryl fluoride 6 E 405 329 -76 1.230
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.262
BrF5 bromine pentafluoride 3 A1 369 299 -70 1.234
ClF3 Chlorine trifluoride 3 A1 328 266 -62 1.233
OClO- Chlorine dioxide anion 2 A1 418 326 -92 1.282
N2O4 Dinitrogen tetroxide 9 B2u 265 212 -53 1.250
N2O3 Dinitrogen trioxide 9 A" 63 139 76 0.454
SF5 Sulfur pentafluoride 3 A1 554 445 -109 1.245
SF5 Sulfur pentafluoride 9 E 387 299 -88 1.294
C3O Tricarbon monoxide 5 Π 109 202 93 0.540
Li2O dilithium oxide 3 Πu 112 79 -32 1.410
GaP Gallium monophosphide 1 Σ 284 407 124 0.696
C3 carbon trimer 3 Πu 63 134 71 0.472
ClOOCl Dichlorine dioxide 1 A 750 1123 373 0.668
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.228
H3O+ hydronium cation 2 A1 954 675 -280 1.414
C2H4O4 Formic acid dimer 2 Ag 2949 1897 -1052 1.554
C2H4O4 Formic acid dimer 18 Bu 2939 2075 -863 1.416
C2H4O4 Formic acid dimer 24 Bu 268 476 208 0.563
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
B2H6 Diborane 14 B2u 369 268 -100 1.374
H2OH2O water dimer 6 A' 311 466 155 0.668
H2OH2O water dimer 7 A' 143 269 126 0.531
H2OH2O water dimer 8 A' 103 205 102 0.502
H2OH2O water dimer 10 A" 523 818 295 0.639
H2OH2O water dimer 11 A" 108 198 90 0.544
H2OH2O water dimer 12 A" 88 160 72 0.550
H2POH Phosphinous acid 9 A" 375 253 -123 1.486
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ClOF3 Chlorine trifluoride oxide 6 A' 224 180 -44 1.241
ZnCH3 Zinc monomethyl 6 E 315 578 263 0.545
ClONO chlorine nitrite 5 A' 270 179 -91 1.511
HSO3 HOSO2 3 A 1296 1041 -255 1.245