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 CCD/3-21G*
Calculated values were scaled by 0.9565.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 358 158 0.558
C2H4+ Ethylene cation 4 Au 84 -200 -284 -0.421
HCN+ hydrogen cyanide cation 1 Σ 3050 3558 508 0.857
HCN+ hydrogen cyanide cation 2 Σ 1800 2764 964 0.651
HNCO Isocyanic acid 4 A' 777 572 -204 1.357
C3F8 perfluoropropane 13 A2 276 203 -73 1.361
C10H8 naphthalene 27 B2g 770 593 -177 1.298
C3H6O 2-Propen-1-ol 22 A 377 300 -77 1.257
C3H6O 2-Propen-1-ol 24 A 188 90 -98 2.098
C5H8 Cyclopentene 18 A' 254 114 -140 2.225
CH2N4 1H-Tetrazole 11 A' 925 732 -193 1.264
C2H2N4 sym-tetrazine 13 B2u 883 477 -406 1.853
C3H6O Oxetane 23 B2 1228 941 -287 1.305
C2H3NO3 Oxamic acid 21 A" 162 107 -55 1.513
C2H3NO3 Oxamic acid 18 A" 745 589 -156 1.265
C2H3NO3 Oxamic acid 17 A" 815 620 -195 1.315
C2H3NO3 Oxamic acid 15 A' 328 261 -67 1.257
C4H2 Diacetylene 9 Πu 231 132 -99 1.751
C4H2 Diacetylene 7 Πg 482 -637 -1119 -0.757
C4H6O2 2,3-Butanedione 21 Bg 240 105 -135 2.284
C4H6O2 2,3-Butanedione 16 Au 48 78 30 0.617
HCNO fulminic acid 5 Π 224 489 264 0.459
HCNO fulminic acid 3 Σ 1254 980 -275 1.280
C2H3NO3 Oxamic acid 3 A' 2600 3394 794 0.766
F2CCCF2 tetrafluoroallene 11 E 90 71 -19 1.259
C5H8 1,4-Pentadiene 16 A 137 294 157 0.466
C5H8 1,4-Pentadiene 17 A 102 78 -24 1.304
C6H8 1,4-Cyclohexadiene 19 B1u 108 79 -29 1.369
H2CS- thioformaldehyde anion 4 B1 450 198 -252 2.274
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.585
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 335 -121 1.363
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 223 79 0.646
FCO+ Carbonyl fluoride cation 3 Π 650 464 -186 1.401
C2H Ethynyl radical 3 Π 372 735 363 0.506
CH3 Methyl radical 2 A2" 606 427 -179 1.419
OH- hydroxide anion 1 Σ 3738 2547 -1191 1.468
OH Hydroxyl radical 1 Σ 3738 3135 -603 1.192
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.645
H2CCCCH2 Butatriene 16 B3g 330 250 -80 1.318
H2CCCCH2 Butatriene 10 B2g 544 278 -266 1.954
HF Hydrogen fluoride 1 Σ 4138 3553 -585 1.165
H2O2 Hydrogen peroxide 4 A 371 119 -252 3.107
HCCN cyanomethylene 5 Π 129 -204 -333 -0.632
CH2OH Hydroxymethyl radical 9 A 234 407 173 0.574
CH3SO2NH2 methanesulfonamide 11 A' 689 522 -167 1.320
HClO4 perchloric acid 12 A" 191 110 -81 1.732
H2O Water 1 A1 3657 2378 -1279 1.538
H2O Water 3 B2 3756 2547 -1209 1.475
O2+ diatomic oxygen cation 1 Σg 1906 1260 -646 1.513
O2 Oxygen diatomic 1 Σg 1484 1176 -308 1.262
FOOF Perfluoroperoxide 1 A 1210 883 -327 1.371
FOOF Perfluoroperoxide 4 A 202 129 -73 1.569
FOOF Perfluoroperoxide 5 B 614 891 277 0.689
BeF2 Beryllium fluoride 3 Πu 343 264 -79 1.300
N2O Nitrous oxide 2 Σ 1298 1030 -268 1.260
N2O Nitrous oxide 3 Π 596 457 -140 1.306
O3 Ozone 3 B2 1042 1902 860 0.548
OClO- Chlorine dioxide anion 1 A1 790 531 -259 1.487
OClO- Chlorine dioxide anion 2 A1 418 321 -97 1.302
NO Nitric oxide 1 Σ 1904 3555 1651 0.536
C3O Tricarbon monoxide 5 Π 109 69 -40 1.583
VO Vanadium monoxide 1 Σ 1011 1556 544 0.650
FO Oxygen monofluoride 1 Σ 1053 1956 903 0.538
C3 carbon trimer 3 Πu 63 -152 -216 -0.416
PS phosphorus sulfide 1 Σ 739 1420 681 0.521
BrNO Nitrosyl bromide 1 A' 1832 1390 -443 1.319
NH2- amino anion 1 A1 3122 2502 -620 1.248
NH2- amino anion 3 B2 3190 2547 -643 1.253
NH Imidogen 1 Σ 3314 2787 -527 1.189
ZnH2 Zinc hydride 2 Σu 1889 1451 -439 1.302
ZnH2 Zinc hydride 3 Πu 633 37 -595 17.071
ClONO2 Chlorine nitrate 9 A" 124 95 -29 1.307
SCN thiocyanato radical 1 Σ 1942 2397 455 0.810
Cl3- trichloride anion 2 Σu 327 255 -72 1.283
CaS Calcium sulfide 1 Σ 462 328 -134 1.409
OPCl Phosphorus oxychloride 2 A' 308 482 174 0.640
OPCl Phosphorus oxychloride 3 A' 492 303 -189 1.621
Na2 Sodium diatomic 1 Σg 159 121 -38 1.317
H2POH Phosphinous acid 9 A" 375 213 -163 1.766
Mg2 Magnesium diatomic 1 Σg 51 29 -22 1.744
ZnCH3 Zinc monomethyl 6 E 315 606 291 0.519
H2COO dioxymethyl 6 A' 908 594 -314 1.529
BrONO Bromine nitrite 1 A' 1723 1364 -359 1.263
ONONO Nitrosyl nitrite 1 A1 1740 1363 -377 1.277
ONONO Nitrosyl nitrite 6 B1 140 107 -33 1.309
ONONO Nitrosyl nitrite 7 B2 1697 1311 -386 1.294
ONONO Nitrosyl nitrite 9 B2 380 604 224 0.629
H3O+ hydronium cation 2 A1 954 291 -663 3.278
PO2 Phosphorus dioxide 3 B2 1328 1758 431 0.755
TiO Titanium monoxide 1 Σ 1009 1608 599 0.628
INO Nitrosyl iodide 1 A' 1785 1413 -372 1.263
INO Nitrosyl iodide 2 A' 216 479 263 0.451
INO Nitrosyl iodide 3 A' 470 227 -243 2.071