return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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 MP3/6-31G*
Calculated values were scaled by 0.9386.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 167 54 0.676
HCN+ hydrogen cyanide cation 1 Σ 3050 3518 468 0.867
HCN+ hydrogen cyanide cation 2 Σ 1800 2715 915 0.663
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
C6H6 Benzene 8 B2g 703 515 -188 1.366
CH3CCH propyne 10 E 328 254 -74 1.290
C2H4+ Ethylene cation 4 Au 84 127 43 0.663
C2H2 Acetylene 4 Πg 612 409 -203 1.496
CHONH2 formamide 12 A" 289 -166 -455 -1.736
C3F8 perfluoropropane 13 A2 276 213 -63 1.296
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.312
C6H4O2 parabenzoquinone 17 B2g 241 185 -56 1.304
C6H5NO2 Nitrobenzene 22 B1 675 511 -164 1.321
CH3COOCH3 methyl acetate 27 A" 110 80 -30 1.382
C10H8 naphthalene 28 B2g 461 310 -151 1.486
C10H8 naphthalene 27 B2g 770 422 -348 1.825
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.780
C6H5Cl chlorobenzene 18 B1 685 509 -176 1.345
C4H8S Thiophene, tetrahydro- 5 A 1464 2943 1479 0.497
C4H8S Thiophene, tetrahydro- 6 A 1441 2943 1502 0.490
C4H8S Thiophene, tetrahydro- 7 A 1321 2919 1598 0.452
C4H8S Thiophene, tetrahydro- 8 A 1276 2919 1643 0.437
C4H8S Thiophene, tetrahydro- 11 A 1023 1454 431 0.704
C4H8S Thiophene, tetrahydro- 12 A 888 1451 563 0.612
C4H8S Thiophene, tetrahydro- 13 A 829 1329 500 0.624
C4H8S Thiophene, tetrahydro- 14 A 822 1306 484 0.630
C4H8S Thiophene, tetrahydro- 15 A 678 1285 607 0.528
C4H8S Thiophene, tetrahydro- 16 A 472 1257 785 0.376
C4H8S Thiophene, tetrahydro- 17 A 290 1209 919 0.240
C5H8 Cyclopentene 18 A' 254 157 -97 1.622
NH2CN cyanamide 5 A' 408 643 235 0.635
C4H6O2 2,3-Butanedione 21 Bg 240 122 -118 1.974
C4H2 Diacetylene 7 Πg 482 294 -188 1.638
C4H2 Diacetylene 8 Πu 630 487 -143 1.293
C6H5F Fluorobenzene 18 B1 685 521 -164 1.316
C2H3NO3 Oxamic acid 3 A' 2600 3442 842 0.755
C2H3NO3 Oxamic acid 16 A" 984 769 -215 1.280
C2H3NO3 Oxamic acid 20 A" 315 239 -76 1.319
C2H3NO3 Oxamic acid 21 A" 162 40 -122 4.049
CH3CCCH3 2-Butyne 16 E" 371 218 -153 1.703
C3H6O Oxetane 18 B1 90 -44 -133 -2.058
C6H4F2 1,4-difluorobenzene 16 B2g 692 516 -176 1.342
C5H8 1,4-Pentadiene 16 A 137 287 150 0.478
HCCCl Chloroacetylene 5 Π 326 230 -96 1.418
C6H6 Benzvalene 10 A1 996 745 -251 1.336
H2CS- thioformaldehyde anion 4 B1 450 -139 -589 -3.237
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.668
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 332 -124 1.375
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.558
NaOH sodium hydroxide 3 Π 300 171 -129 1.757
CN Cyano radical 1 Σ 2069 2516 447 0.822
C2H Ethynyl radical 2 Σ 1841 2260 420 0.814
C2H Ethynyl radical 3 Π 372 734 362 0.507
CH3 Methyl radical 2 A2" 606 395 -212 1.536
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 118 -146 2.235
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 86 -272 4.172
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 859 -277 1.323
CH2OH Hydroxymethyl radical 9 A 234 416 182 0.562
CH2OH Hydroxymethyl radical 8 A 482 713 231 0.676
HCCN cyanomethylene 5 Π 129 -470 -598 -0.275
CHCl2 dichloromethyl radical 4 A' 190 297 107 0.639
C2Cl2 dichloroacetylene 4 Πg 333 202 -131 1.650
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.347
O3 Ozone 3 B2 1042 1694 652 0.615
NO Nitric oxide 1 Σ 1904 2971 1067 0.641
NO2 Nitrogen dioxide 1 A1 1318 4980 3662 0.265
NO2 Nitrogen dioxide 2 A1 750 -8584 -9334 -0.087
NO2 Nitrogen dioxide 3 B2 1618 11575 9957 0.140
N2O3 Dinitrogen trioxide 9 A" 63 130 67 0.484
VO Vanadium monoxide 1 Σ 1011 1782 771 0.567
SiP Silicon monophosphide 1 Σ 616 1000 384 0.616
C3 carbon trimer 3 Πu 63 93 30 0.682
ZnH2 Zinc hydride 3 Πu 633 487 -145 1.298
PO Phosphorus monoxide 1 Σ 1233 2725 1492 0.453
AlO Aluminum monoxide 1 Σ 979 756 -223 1.295
ClOO chloroperoxy radical 2 A' 414 1010 596 0.410
ClOO chloroperoxy radical 3 A' 201 466 265 0.432
Cl3- trichloride anion 2 Σu 327 246 -81 1.328
CaS Calcium sulfide 1 Σ 462 347 -116 1.333
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.945
ZnCH3 Zinc monomethyl 6 E 315 597 282 0.527
H2POH Phosphinous acid 9 A" 375 254 -122 1.480
OPCl Phosphorus oxychloride 3 A' 492 301 -191 1.635
OPCl Phosphorus oxychloride 2 A' 308 493 185 0.625
PN+ phosphorus nitride cation 1 Σ 1200 2379 1179 0.504
ONONO Nitrosyl nitrite 9 B2 380 590 210 0.644
ZnCN Zinc monocyanide 3 Π 212 80 -132 2.638
ClONO chlorine nitrite 4 A' 406 603 197 0.673