return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) 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 MP2/aug-cc-pVDZ
Calculated values were scaled by 0.959.

Species Name mode Symmetry Experiment Theory difference ratio
CH3CONH2 Acetamide 20 A 259 89 -170 2.904
CH3OH Methyl alcohol 12 A" 200 299 99 0.668
CH3COCH3 Acetone 12 A2 77 20 -57 3.834
C2H4+ Ethylene cation 4 Au 84 -100 -184 -0.842
C2H2 Acetylene 4 Πg 612 392 -220 1.563
CH3CCH propyne 10 E 328 254 -74 1.292
CHONH2 formamide 12 A" 289 167 -122 1.727
CH3NO2 Methane, nitro- 11 A" 1583 3094 1511 0.512
CBr2F2 Methane, dibromodifluoro- 3 A1 140 333 193 0.421
CH3COOCH3 methyl acetate 27 A" 110 47 -63 2.348
CF2CCl2 difluorodichloroethylene 7 B1 1327 547 -780 2.425
CF2CCl2 difluorodichloroethylene 8 B1 989 304 -685 3.253
CF2CCl2 difluorodichloroethylene 11 B2 564 441 -123 1.278
CF2CCl2 difluorodichloroethylene 12 B2 323 175 -148 1.841
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.757
C3H2N2 Malononitrile 6 A1 167 132 -35 1.261
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 316 -893 3.828
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 396 -137 1.347
C6F6 hexafluorobenzene 7 B2g 715 447 -268 1.601
C6F6 hexafluorobenzene 8 B2g 243 172 -71 1.413
C6F6 hexafluorobenzene 20 E2u 175 131 -44 1.338
NH2CN cyanamide 5 A' 408 644 236 0.634
C4H6O2 2,3-Butanedione 21 Bg 240 125 -115 1.922
C4H2 Diacetylene 7 Πg 482 -626 -1108 -0.770
C4H2 Diacetylene 8 Πu 630 488 -142 1.292
C4H2 Diacetylene 9 Πu 231 145 -86 1.593
C2H3NO3 Oxamic acid 3 A' 2600 3452 852 0.753
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 17 A" 815 643 -172 1.267
C2H3NO3 Oxamic acid 21 A" 162 61 -101 2.657
CH3CCCH3 2-Butyne 16 E" 371 210 -161 1.763
C3H6O Oxetane 18 B1 90 -96 -186 -0.933
C3H6O Oxetane 23 B2 1228 980 -248 1.254
HCNO fulminic acid 5 Π 224 -350 -574 -0.641
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
HCCCl Chloroacetylene 5 Π 326 244 -82 1.336
CH3ONO Methyl nitrite 15 A" 186 75 -111 2.468
CH3SSCH3 Disulfide, dimethyl 13 A 117 91 -26 1.292
CO+ carbon monoxide cation 1 Σ 2214 2732 518 0.811
HCCCN Cyanoacetylene 7 Π 222 167 -55 1.327
SiF2+ Silicon difluoride cation 2 A1 350 274 -76 1.276
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.357
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 134 -37 1.277
CN Cyano radical 1 Σ 2069 2722 654 0.760
C6H5O phenoxy radical 4 A1 1550 3117 1567 0.497
C6H5O phenoxy radical 5 A1 1481 3094 1613 0.479
C6H5O phenoxy radical 11 A1 515 745 230 0.691
C6H5O phenoxy radical 23 B2 1515 3100 1585 0.489
C2H Ethynyl radical 2 Σ 1841 2346 506 0.784
C2H Ethynyl radical 3 Π 372 721 350 0.515
CH3OO methylperoxy radical 12 A" 170 127 -43 1.335
CH3 Methyl radical 2 A2" 606 474 -132 1.278
CH2OH Hydroxymethyl radical 9 A 234 421 187 0.556
CH3CO Acetyl radical 4 A' 1420 3049 1629 0.466
CCl3 Trichloromethyl radical 2 A1 251 366 115 0.686
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.643
C4H6 Methylenecyclopropane 17 B1 360 252 -108 1.429
C2Cl2 dichloroacetylene 4 Πg 333 111 -222 2.987
O2+ diatomic oxygen cation 1 Σg 1906 1391 -515 1.370
FOOF Perfluoroperoxide 1 A 1210 1716 506 0.705
FOOF Perfluoroperoxide 3 A 360 255 -105 1.412
FOOF Perfluoroperoxide 4 A 202 138 -64 1.468
O3 Ozone 3 B2 1042 2189 1147 0.476
NO Nitric oxide 1 Σ 1904 3519 1615 0.541
NO2 Nitrogen dioxide 3 B2 1618 2392 774 0.677
N2O3 Dinitrogen trioxide 9 A" 63 160 97 0.393
VO Vanadium monoxide 1 Σ 1011 2112 1101 0.479
FO Oxygen monofluoride 1 Σ 1053 2244 1191 0.469
C3 carbon trimer 3 Πu 63 -49 -113 -1.287
SF5Cl sulfur chloropentafluoride 5 B1 625 433 -192 1.443
SF5Cl sulfur chloropentafluoride 7 B2 505 305 -200 1.656
SF5Cl sulfur chloropentafluoride 11 E 397 242 -155 1.641
AlO Aluminum monoxide 1 Σ 979 626 -353 1.564
C2H4O4 Formic acid dimer 13 Au 1050 66 -984 15.941
SCN thiocyanato radical 1 Σ 1942 2419 477 0.803
ClOO chloroperoxy radical 2 A' 414 1044 631 0.396
ClOO chloroperoxy radical 3 A' 201 485 283 0.416
H2POH Phosphinous acid 9 A" 375 245 -130 1.531
AsN Arsenic mononitride 1 Σ 1069 809 -260 1.321
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.908
ClOF3 Chlorine trifluoride oxide 5 A' 319 244 -75 1.308
ClOF3 Chlorine trifluoride oxide 9 A" 412 313 -99 1.318
BrONO2 Bromine nitrate 5 A' 564 440 -124 1.282
ClONO chlorine nitrite 4 A' 406 297 -109 1.369
CH3BO Borane, methyloxo- 7 E 897 1390 494 0.645
BrONO Bromine nitrite 4 A' 391 293 -99 1.337
ONONO Nitrosyl nitrite 9 B2 380 -148 -528 -2.564