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 HF/6-311G**
Calculated values were scaled by 0.9085.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 171 58 0.661
CH3CONH2 Acetamide 20 A 259 190 -68 1.360
CH3OH Methyl alcohol 12 A" 200 304 104 0.657
C2H4+ Ethylene cation 4 Au 84 341 257 0.247
CHONH2 formamide 12 A" 289 118 -171 2.454
CBr2F2 Methane, dibromodifluoro- 3 A1 140 338 198 0.414
CH3COOCH3 methyl acetate 27 A" 110 80 -30 1.383
CF2CCl2 difluorodichloroethylene 7 B1 1327 664 -663 1.998
CF2CCl2 difluorodichloroethylene 8 B1 989 334 -655 2.961
CF2CCl2 difluorodichloroethylene 12 B2 323 186 -137 1.734
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.681
C5H8 Cyclopentene 18 A' 254 147 -107 1.732
C2H2N4 sym-tetrazine 18 B3u 254 373 119 0.681
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 604 253 0.581
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 358 -851 3.378
NH2CN cyanamide 5 A' 408 619 211 0.659
C4H6O2 2,3-Butanedione 21 Bg 240 120 -120 2.000
C6H4 Benzyne 24 B2 472 295 -177 1.598
C2H3NO3 Oxamic acid 3 A' 2600 3478 878 0.748
C2H3NO3 Oxamic acid 21 A" 162 51 -111 3.201
HCNO fulminic acid 5 Π 224 553 329 0.405
C5H8 1,4-Pentadiene 16 A 137 291 154 0.470
C2F2 difluoroacetylene 4 Πg 270 471 201 0.573
ZnO zinc monoxide 1 Σ 720 369 -351 1.951
ZnS Zinc sulfide 1 Σ 459 303 -156 1.517
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 122 -49 1.402
C2H Ethynyl radical 3 Π 372 543 171 0.685
C2H+ Ethynyl cation 3 Π 550 852 302 0.645
CH3 Methyl radical 2 A2" 606 342 -265 1.774
CH2OH Hydroxymethyl radical 8 A 482 727 245 0.663
CH2OH Hydroxymethyl radical 9 A 234 376 142 0.622
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 855 -281 1.329
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 129 -135 2.043
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 90 -268 3.977
CH3CO Acetyl radical 4 A' 1420 2964 1544 0.479
CHCl2 dichloromethyl radical 4 A' 190 294 104 0.646
CuCl Copper monochloride 1 Σ 418 304 -113 1.372
FOOF Perfluoroperoxide 2 A 630 1035 405 0.608
FOOF Perfluoroperoxide 3 A 360 517 157 0.696
FOOF Perfluoroperoxide 5 B 614 1025 411 0.599
CaF2 Calcium difluoride 2 A1 120 34 -86 3.489
ZnCl Zinc monochloride 1 Σ 391 278 -112 1.403
PCl5 Phosphorus pentachloride 2 A1' 370 269 -101 1.377
N2O4 Dinitrogen tetroxide 3 Ag 265 421 156 0.629
N2O3 Dinitrogen trioxide 6 A' 241 403 162 0.598
N2O3 Dinitrogen trioxide 7 A' 205 336 131 0.611
N2O3 Dinitrogen trioxide 8 A" 414 624 210 0.663
N2O3 Dinitrogen trioxide 9 A" 63 115 52 0.547
NS Mononitrogen monosulfide 1 Σ 1219 816 -403 1.493
VO Vanadium monoxide 1 Σ 1011 497 -514 2.033
C3 carbon trimer 3 Πu 63 115 51 0.552
SiP Silicon monophosphide 1 Σ 616 415 -201 1.484
CaOH Calcium monohydroxide 2 Σ 353 594 241 0.594
CaOH Calcium monohydroxide 3 Π 609 404 -205 1.509
Cu2 Copper dimer 1 Σg 265 175 -89 1.510
PS phosphorus sulfide 1 Σ 739 477 -262 1.549
S3- Sulfur trimer anion 3 B2 594 408 -186 1.457
BH3CO Borane carbonyl 4 A1 691 501 -190 1.380
SF5Cl sulfur chloropentafluoride 7 B2 505 336 -169 1.504
SF5Cl sulfur chloropentafluoride 11 E 397 262 -135 1.517
HOClO Chlorous acid 3 A 978 741 -238 1.321
ZnH Zinc monohydride 1 Σ 1608 1087 -520 1.478
AlO Aluminum monoxide 1 Σ 979 733 -247 1.337
C2H4O4 Formic acid dimer 13 Au 1050 68 -982 15.374
C2H4O4 Formic acid dimer 17 Bu 3084 3511 427 0.878
C2H4O4 Formic acid dimer 24 Bu 268 199 -69 1.346
Cl3- trichloride anion 2 Σu 327 -144 -471 -2.274
F3- trifluoride anion 2 Σu 550 -209 -759 -2.626
H2POH Phosphinous acid 9 A" 375 256 -120 1.468
Mg2 Magnesium diatomic 1 Σg 51 4 -47 14.001
ZnCH3 Zinc monomethyl 3 A1 445 242 -203 1.842
ZnCH3 Zinc monomethyl 6 E 315 572 257 0.551
NNS Nitrogen sulfide 2 Σ 752 519 -233 1.448
ClONO chlorine nitrite 4 A' 406 672 266 0.604
CH3BO Borane, methyloxo- 7 E 897 1429 532 0.627
HSO3 HOSO2 4 A 1097 826 -271 1.329
ONONO Nitrosyl nitrite 9 B2 380 712 332 0.534