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 B3PW91/3-21G*
Calculated values were scaled by 0.9594.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 371 171 0.538
CH3COCH3 Acetone 12 A2 77 61 -16 1.260
CH3CONH2 Acetamide 20 A 259 400 141 0.648
C2H4+ Ethylene cation 4 Au 84 -511 -595 -0.165
HNCO Isocyanic acid 4 A' 777 575 -201 1.350
HNCO Isocyanic acid 5 A' 577 445 -132 1.298
CHONH2 formamide 12 A" 289 496 208 0.581
CH3COOCH3 methyl acetate 26 A" 136 73 -63 1.869
CH3COOCH3 methyl acetate 27 A" 110 62 -48 1.788
C3F8 perfluoropropane 13 A2 276 202 -74 1.365
CH3OCHO methyl formate 18 A" 130 73 -57 1.778
C2H2O2 Ethanedial 7 Au 127 195 68 0.651
C3H6O 2-Propen-1-ol 24 A 188 100 -88 1.888
C3H6O 2-Propen-1-ol 22 A 377 298 -79 1.265
C4H8S Thiophene, tetrahydro- 5 A 1464 2958 1494 0.495
C4H8S Thiophene, tetrahydro- 6 A 1441 2958 1517 0.487
C4H8S Thiophene, tetrahydro- 7 A 1321 2949 1628 0.448
C4H8S Thiophene, tetrahydro- 8 A 1276 2948 1672 0.433
C4H8S Thiophene, tetrahydro- 11 A 1023 1465 442 0.698
C4H8S Thiophene, tetrahydro- 12 A 888 1462 574 0.607
C4H8S Thiophene, tetrahydro- 13 A 829 1329 500 0.624
C4H8S Thiophene, tetrahydro- 14 A 822 1315 493 0.625
C4H8S Thiophene, tetrahydro- 15 A 678 1279 601 0.530
C4H8S Thiophene, tetrahydro- 16 A 472 1273 801 0.371
C4H8S Thiophene, tetrahydro- 17 A 290 1223 933 0.237
C4H8O2 1,4-Dioxane 19 Au 288 221 -67 1.306
C4H9N Pyrrolidine 36 A" 65 29 -36 2.241
C5H8 Cyclopentene 18 A' 254 125 -129 2.030
N2H4 Hydrazine 6 A 780 601 -179 1.298
C2N2 Cyanogen 4 Πg 503 760 257 0.662
C4H6O2 2,3-Butanedione 16 Au 48 35 -13 1.391
C4H6O2 2,3-Butanedione 21 Bg 240 59 -181 4.064
C5H12 Propane, 2,2-dimethyl- 12 T1 203 320 117 0.635
C2H3NO3 Oxamic acid 15 A' 328 253 -75 1.295
C2H3NO3 Oxamic acid 21 A" 162 114 -48 1.424
C3O2 Carbon suboxide 7 Πu 61 146 85 0.417
HCNO fulminic acid 5 Π 224 529 305 0.424
C2H3NO3 Oxamic acid 3 A' 2600 3380 780 0.769
C3H6O Oxetane 23 B2 1228 950 -278 1.293
Zn(CH3)2 dimethyl zinc 11 E' 134 -104 -238 -1.285
C5H8 1,4-Pentadiene 16 A 137 300 163 0.457
C5H8 1,4-Pentadiene 17 A 102 79 -23 1.289
CH3ONO Methyl nitrite 15 A" 186 135 -51 1.374
C6H6 Benzvalene 10 A1 996 777 -219 1.282
H2CS- thioformaldehyde anion 4 B1 450 248 -202 1.816
LiOH lithium hydroxide 3 Π 257 399 142 0.643
SiF2+ Silicon difluoride cation 2 A1 350 275 -75 1.275
C4N2 2-Butynedinitrile 6 Πg 504 909 405 0.554
C4N2 2-Butynedinitrile 8 Πu 472 687 215 0.687
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.330
CCl2 dichloromethylene 3 B2 758 601 -157 1.261
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 219 75 0.659
CuO Copper Monoxide 1 Σ 640 917 277 0.698
FCO+ Carbonyl fluoride cation 3 Π 650 499 -151 1.302
C2H Ethynyl radical 3 Π 372 538 167 0.690
CH3 Methyl radical 2 A2" 606 472 -134 1.284
CH3OO methylperoxy radical 12 A" 170 136 -34 1.253
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 866 -270 1.311
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 143 -121 1.840
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 97 -261 3.690
CH2OH Hydroxymethyl radical 9 A 234 407 173 0.576
OH- hydroxide anion 1 Σ 3738 2652 -1086 1.410
NF2 Difluoroamino radical 2 A1 573 457 -116 1.254
CH3SO2NH2 methanesulfonamide 11 A' 689 497 -192 1.385
HNCS Isothiocyanic acid 5 A' 469 144 -325 3.248
OH Hydroxyl radical 1 Σ 3738 3175 -563 1.177
C2Cl2 dichloroacetylene 4 Πg 333 493 160 0.675
HCCN cyanomethylene 4 Π 383 589 206 0.650
HCCN cyanomethylene 5 Π 129 360 231 0.358
NF3 Nitrogen trifluoride 4 E 492 388 -104 1.269
HF Hydrogen fluoride 1 Σ 4138 3544 -594 1.168
BeF2 Beryllium fluoride 3 Πu 343 257 -86 1.333
CaF2 Calcium difluoride 2 A1 120 28 -92 4.225
HClO4 perchloric acid 12 A" 191 131 -60 1.462
FOOF Perfluoroperoxide 1 A 1210 943 -267 1.283
FOOF Perfluoroperoxide 5 B 614 913 299 0.673
H2O2 Hydrogen peroxide 4 A 371 64 -307 5.791
OClO- Chlorine dioxide anion 2 A1 418 333 -85 1.257
NO2 Nitrogen dioxide 1 A1 1318 659 -659 2.000
NH3 Ammonia 2 A1 950 689 -261 1.378
O3 Ozone 2 A1 705 557 -148 1.265
O2+ diatomic oxygen cation 1 Σg 1906 1422 -483 1.340
ClF3 Chlorine trifluoride 6 B2 442 351 -91 1.258
C3O Tricarbon monoxide 5 Π 109 193 84 0.565
ND3 Ammonia-d3 2 A1 748 527 -221 1.420
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.418
Li2O dilithium oxide 3 Πu 112 67 -44 1.658
C3 carbon trimer 3 Πu 63 151 87 0.421
N2O4 Dinitrogen tetroxide 9 B2u 265 187 -78 1.415
TiO2 Titanium dioxide 1 A1 959 351 -608 2.733
FO2 Dioxygen monofluoride 1 A' 1487 1100 -387 1.352
NH2- amino anion 1 A1 3122 2573 -549 1.213
NH2- amino anion 3 B2 3190 2613 -578 1.221
H3O+ hydronium cation 2 A1 954 480 -475 1.990
C2H4O4 Formic acid dimer 24 Bu 268 441 173 0.608
Na2 Sodium diatomic 1 Σg 159 255 96 0.625
Mg2 Magnesium diatomic 1 Σg 51 113 62 0.453
OPCl Phosphorus oxychloride 2 A' 308 469 161 0.657
OPCl Phosphorus oxychloride 3 A' 492 288 -204 1.710
C2H4O4 Formic acid dimer 2 Ag 2949 1978 -971 1.491
C2H4O4 Formic acid dimer 18 Bu 2939 2252 -687 1.305
ClONO chlorine nitrite 5 A' 270 215 -55 1.257
H2POH Phosphinous acid 9 A" 375 221 -154 1.695
ZnCH3 Zinc monomethyl 6 E 315 635 320 0.496
H2OH2O water dimer 6 A' 311 548 237 0.568
H2OH2O water dimer 7 A' 143 290 147 0.494
INO Nitrosyl iodide 2 A' 216 510 294 0.423
INO Nitrosyl iodide 3 A' 470 259 -211 1.814
H2OH2O water dimer 8 A' 103 207 104 0.498
H2OH2O water dimer 10 A" 523 876 353 0.597
H2OH2O water dimer 11 A" 108 228 120 0.473
HSO3 HOSO2 3 A 1296 1034 -262 1.254
ClOO chloroperoxy radical 1 A' 1443 1090 -353 1.323
ONONO Nitrosyl nitrite 9 B2 380 593 213 0.640