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/cc-pVTZ
Calculated values were scaled by 0.9885.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 298 98 0.671
C3H6O 2-Propen-1-ol 24 A 188 118 -70 1.599
C4H6O2 2,3-Butanedione 13 Au 1111 877 -234 1.266
C4H6O2 2,3-Butanedione 16 Au 48 31 -17 1.545
C4H6O2 2,3-Butanedione 21 Bg 240 79 -161 3.020
C5H12 Propane, 2,2-dimethyl- 12 T1 203 324 121 0.626
C2H3NO3 Oxamic acid 3 A' 2600 3429 829 0.758
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.278
C2H3NO3 Oxamic acid 21 A" 162 81 -81 2.005
C3H6O Oxetane 12 A2 986 798 -188 1.236
C3H6O Oxetane 18 B1 90 -70 -159 -1.289
HCNO fulminic acid 5 Π 224 -47 -271 -4.741
C5H8 1,4-Pentadiene 16 A 137 290 153 0.473
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 180 -47 1.258
CH3SSCH3 Disulfide, dimethyl 13 A 117 87 -30 1.349
C6H6 Benzvalene 10 A1 996 746 -250 1.335
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 138 -32 1.235
H2CS- thioformaldehyde anion 4 B1 450 258 -192 1.746
SiF2+ Silicon difluoride cation 2 A1 350 265 -85 1.321
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 219 75 0.657
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.327
C2H Ethynyl radical 3 Π 372 268 -104 1.389
CH3OO methylperoxy radical 12 A" 170 117 -53 1.448
CH2OH Hydroxymethyl radical 9 A 234 348 114 0.673
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 878 -258 1.294
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 161 -103 1.637
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 105 -253 3.422
HCCN cyanomethylene 5 Π 129 -72 -201 -1.783
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.273
HClO4 perchloric acid 12 A" 191 152 -39 1.256
N2O4 Dinitrogen tetroxide 9 B2u 265 216 -49 1.226
N2O3 Dinitrogen trioxide 9 A" 63 147 84 0.430
C3 carbon trimer 3 Πu 63 -90 -153 -0.706
B2Cl4 Diboron tetrachloride 9 E 104 84 -20 1.236
SiH- silicon monohydride anion 1 Σ 2175 1762 -413 1.234
H3O+ hydronium cation 2 A1 954 729 -226 1.310
C2H4O4 Formic acid dimer 2 Ag 2949 1963 -986 1.502
C2H4O4 Formic acid dimer 18 Bu 2939 2165 -773 1.357
C2H4O4 Formic acid dimer 24 Bu 268 458 190 0.585
ClOO chloroperoxy radical 3 A' 201 323 122 0.623
B2H6 Diborane 14 B2u 369 267 -102 1.381
H2OH2O water dimer 6 A' 311 471 160 0.661
H2OH2O water dimer 7 A' 143 268 125 0.534
H2OH2O water dimer 8 A' 103 155 52 0.663
H2OH2O water dimer 10 A" 523 774 251 0.675
H2OH2O water dimer 11 A" 108 180 72 0.600
H2OH2O water dimer 12 A" 88 50 -38 1.754
H2POH Phosphinous acid 9 A" 375 258 -118 1.457
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ClONO chlorine nitrite 5 A' 270 185 -85 1.462
ZnCN Zinc monocyanide 3 Π 212 166 -46 1.280