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 HF/6-31G**
Calculated values were scaled by 0.9026.

Species Name mode Symmetry Experiment Theory difference ratio
CH3SeH Methane selenol 12 A" 145 209 64 0.693
C3H4O2 β–Propiolactone 21 A" 113 172 59 0.657
CH3CONH2 Acetamide 20 A 259 115 -144 2.260
CH3OH Methyl alcohol 12 A" 200 308 108 0.650
CH3COCH3 Acetone 12 A2 77 48 -29 1.608
C2Cl6 hexachloroethane 12 Eu 114 164 50 0.693
C2H4+ Ethylene cation 4 Au 84 348 264 0.242
CHONH2 formamide 12 A" 289 178 -110 1.620
CH3COCH2CH3 2-Butanone 33 A" 87 28 -59 3.134
C3H6O 2-Propen-1-ol 24 A 188 109 -79 1.721
C4H8S Thiophene, tetrahydro- 5 A 1464 2912 1448 0.503
C4H8S Thiophene, tetrahydro- 6 A 1441 2911 1470 0.495
C4H8S Thiophene, tetrahydro- 7 A 1321 2886 1565 0.458
C4H8S Thiophene, tetrahydro- 8 A 1276 2884 1608 0.442
C4H8S Thiophene, tetrahydro- 11 A 1023 1460 437 0.701
C4H8S Thiophene, tetrahydro- 12 A 888 1458 570 0.609
C4H8S Thiophene, tetrahydro- 13 A 829 1349 520 0.615
C4H8S Thiophene, tetrahydro- 14 A 822 1327 505 0.619
C4H8S Thiophene, tetrahydro- 15 A 678 1302 624 0.521
C4H8S Thiophene, tetrahydro- 16 A 472 1273 801 0.371
C4H8S Thiophene, tetrahydro- 17 A 290 1221 931 0.238
C5H8 Cyclopentene 18 A' 254 132 -122 1.917
C2H2N4 sym-tetrazine 18 B3u 254 369 115 0.688
NH2CN cyanamide 5 A' 408 589 181 0.693
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.014
C6H4 Benzyne 24 B2 472 283 -189 1.670
C2H3NO3 Oxamic acid 3 A' 2600 3474 874 0.748
C2H3NO3 Oxamic acid 21 A" 162 51 -111 3.184
HCNO fulminic acid 5 Π 224 553 329 0.405
C5H8 1,4-Pentadiene 16 A 137 289 152 0.475
C2F2 difluoroacetylene 4 Πg 270 412 142 0.656
H2CS- thioformaldehyde anion 4 B1 450 -188 -638 -2.396
CaO Calcium monoxide 1 Σ 732 525 -207 1.395
NaOH sodium hydroxide 3 Π 300 211 -89 1.420
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 122 -49 1.406
C2H+ Ethynyl cation 3 Π 550 838 289 0.655
CH3 Methyl radical 2 A2" 606 307 -299 1.973
CH2OH Hydroxymethyl radical 8 A 482 747 265 0.645
CH2OH Hydroxymethyl radical 9 A 234 366 132 0.640
ClCO carbonyl monochloride 3 A' 335 175 -160 1.915
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 126 -138 2.100
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 88 -270 4.056
HCCN cyanomethylene 5 Π 129 -394 -523 -0.327
HNCS Isothiocyanic acid 5 A' 469 301 -168 1.557
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.648
FOOF Perfluoroperoxide 2 A 630 1033 403 0.610
FOOF Perfluoroperoxide 5 B 614 1025 411 0.599
N2O4 Dinitrogen tetroxide 3 Ag 265 416 151 0.637
N2O4 Dinitrogen tetroxide 4 Au 82 59 -23 1.395
N2O3 Dinitrogen trioxide 6 A' 241 405 164 0.595
N2O3 Dinitrogen trioxide 7 A' 205 337 132 0.609
N2O3 Dinitrogen trioxide 8 A" 414 620 206 0.668
N2O3 Dinitrogen trioxide 9 A" 63 104 41 0.607
NS Mononitrogen monosulfide 1 Σ 1219 807 -412 1.511
SiN Silicon nitride 1 Σ 1151 826 -326 1.394
VO Vanadium monoxide 1 Σ 1011 539 -472 1.876
C3 carbon trimer 3 Πu 63 138 74 0.460
SiP Silicon monophosphide 1 Σ 616 423 -193 1.456
MgOH magnesium hydroxide 3 Π 188 125 -63 1.503
PS phosphorus sulfide 1 Σ 739 494 -245 1.496
CP Carbon monophosphide 1 Σ 1240 912 -328 1.359
BH3CO Borane carbonyl 4 A1 691 490 -201 1.410
H3O+ hydronium cation 2 A1 954 705 -250 1.354
AlO Aluminum monoxide 1 Σ 979 731 -249 1.341
ClOO chloroperoxy radical 1 A' 1443 1075 -368 1.342
ClOO chloroperoxy radical 2 A' 414 645 231 0.642
ClOO chloroperoxy radical 3 A' 201 409 208 0.492
PN+ phosphorus nitride cation 1 Σ 1200 684 -516 1.755
Cl3- trichloride anion 2 Σu 327 43 -284 7.578
OPCl Phosphorus oxychloride 2 A' 308 486 178 0.634
OPCl Phosphorus oxychloride 3 A' 492 313 -179 1.571
F3- trifluoride anion 2 Σu 550 -268 -818 -2.052
H2POH Phosphinous acid 9 A" 375 268 -108 1.402
Mg2 Magnesium diatomic 1 Σg 51 337 286 0.152
ZnCH3 Zinc monomethyl 6 E 315 585 270 0.539
H2COO dioxymethyl 6 A' 908 474 -434 1.917
NNS Nitrogen sulfide 2 Σ 752 529 -223 1.422
ClONO chlorine nitrite 4 A' 406 685 279 0.593
ONONO Nitrosyl nitrite 9 B2 380 713 333 0.533