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Bad vibrational frequency predictions

19 02 11 15 45

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 B2PLYP=FULLultrafine/aug-cc-pVTZ
Calculated values were scaled by 0.9591.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 176 63 0.643
C4H10O Ethoxy ethane 12 A1 240 186 -54 1.291
C4H10O Ethoxy ethane 20 A2 137 96 -41 1.434
CH3CONH2 Acetamide 20 A 259 159 -100 1.625
CH3COOH Acetic acid 18 torsion A" 93 70 -23 1.335
C2H6O2S Dimethyl sulfone 20 B1 262 200 -62 1.311
C2H4+ Ethylene cation 4 torsion Au 84 -421 -505 -0.200
CHONH2 formamide 12 torsion A" 289 206 -83 1.401
CH3SCH3+ dimethyl sulfide cation 15 B1 172 131 -41 1.310
C3F8 perfluoropropane 13 A2 276 217 -59 1.271
CH3COOCH3 methyl acetate 27 torsion A" 110 46 -64 2.392
CH3CH2CH2Br n-propyl bromide 27 torsion A" 133 105 -28 1.264
C3H6O 2-Propen-1-ol 24 A 188 109 -79 1.720
CH2ClCHO chloroacetaldehyde 15 torsion A 27 45 18 0.598
CH2ClCHO chloroacetaldehyde 15 A" 59 166 107 0.355
C5H12 Pentane 23 A2 131 99 -32 1.317
C4H8O Furan, tetrahydro- 33 B 137 53 -84 2.587
C3F6 hexafluoropropene 21 A" 60 39 -21 1.527
C4H8 cyclobutane 6 torsion A1 199 702 503 0.284
C4H8 cyclobutane 16 B2 625 485 -140 1.288
C2H2N2S 1,3,4-Thiadiazole 4 A1 1224 956 -268 1.281
C2H2N2S 1,3,4-Thiadiazole 6 A1 894 598 -296 1.494
C4H6O2 2,3-Butanedione 21 torsion Bg 240 111 -129 2.167
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 991 -400 1.404
C3H6O Oxetane 18 B1 90 -42 -132 -2.117
HCNO fulminic acid 5 torsion Π 224 -71 -295 -3.168
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 669 -2410 4.601
C5H8 1,4-Pentadiene 16 A 137 292 155 0.470
C5H8 1,4-Pentadiene 33 torsion B 331 99 -232 3.330
HCCCHO 2-propynal 9 A' 261 203 -58 1.287
C6H6 Benzvalene 10 A1 996 740 -256 1.346
H2CS- thioformaldehyde anion 4 B1 450 299 -151 1.505
NaOH sodium hydroxide 3 torsion Π 300 215 -85 1.392
SiF2+ Silicon difluoride cation 2 A1 350 273 -77 1.281
CFCl2 dichlorofluoromethyl radical 2 A' 747 581 -166 1.285
C2H+ Ethynyl cation 3 Π 550 823 273 0.668
CH3OO methylperoxy radical 12 torsion A" 170 128 -42 1.330
CH2OH Hydroxymethyl radical 9 torsion A 234 407 173 0.575
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 865 -271 1.313
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 151 -113 1.746
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 104 -254 3.455
HCCN cyanomethylene 5 Π 129 -296 -425 -0.435
HO2 Hydroperoxy radical 1 A' 3436 2268 -1168 1.515
HO2 Hydroperoxy radical 3 A' 1098 638 -460 1.721
CHCl2 dichloromethyl radical 4 A' 190 292 102 0.652
C4H6 Methylenecyclopropane 17 B1 360 281 -79 1.281
CH2Cl chloromethyl radical 4 B1 402 145 -257 2.763
C2Cl2+ dichloroacetylene cation 5 Πu 233 180 -53 1.294
S8 Octasulfur 8 E2 152 232 80 0.656
S8 Octasulfur 9 E2 56 140 84 0.400
N2O4 Dinitrogen tetroxide 9 B2u 265 210 -55 1.263
N2O3 Dinitrogen trioxide 9 torsion A" 63 141 78 0.446
AsSe Arsenic monoselenide 1 Σ 280 495 215 0.566
SiC2 Silicon dicarbide 3 B2 196 153 -43 1.279
C3 carbon trimer 3 Πu 63 135 72 0.469
S3 Sulfur trimer 2 A1 281 556 275 0.505
SiH2D2 silane-d2 6 B1 2183 1573 -610 1.388
SiH2D2 silane-d2 8 B2 1601 2177 576 0.736
GeF Germanium monofluoride 1 Σ 809 626 -183 1.292
ClOO chloroperoxy radical 2 A' 414 776 363 0.533
ClOO chloroperoxy radical 3 A' 201 436 235 0.462
B4H10 Tetraborane(10) 10 A1 827 658 -169 1.256
B4H10 Tetraborane(10) 11 A1 785 550 -235 1.427
B4H10 Tetraborane(10) 12 A1 559 219 -340 2.552
B4H10 Tetraborane(10) 19 A2 662 406 -256 1.631
B4H10 Tetraborane(10) 36 B2 236 353 117 0.668
Cl3- trichloride anion 2 Σu 327 257 -70 1.273
NH2BHNH2 diaminoborane 17 B2 1351 1055 -296 1.280
B5H9 pentaborane9 13 B1 240 593 353 0.405
B5H9 pentaborane9 16 B2 1036 784 -252 1.322
B5H9 pentaborane9 18 B2 600 462 -138 1.300
B5H9 pentaborane9 22 E 1409 1045 -364 1.348
AlP Aluminum monophosphide 1 Σ 379 561 182 0.676
OPCl Phosphorus oxychloride 2 A' 308 470 162 0.655
OPCl Phosphorus oxychloride 3 A' 492 287 -205 1.713
H2POH Phosphinous acid 9 A" 375 257 -119 1.462
C4O4-- squarate dianion 5 B1g 1123 1527 404 0.735
C4O4-- squarate dianion 6 B1g 294 600 306 0.490
BrO3- Bromate anion 4 E 413 323 -90 1.277
CHFCl Chlorofluoromethyl radical 6 A 540 392 -148 1.378
ZnCH3 Zinc monomethyl 6 E 315 579 264 0.544
H2CNCN cyanamide, methylene 3 A' 2208 2972 764 0.743
H2CNCN cyanamide, methylene 4 A' 1621 2155 534 0.752
C2H3NO Nitrosoethylene 11 A' 490 338 -152 1.449
SNO Nitrogen oxide sulfide 3 A' 792 511 -281 1.550
ONNO NO dimer 2 A1 239 353 114 0.678
ONNO NO dimer 3 A1 135 287 152 0.469
ONNO NO dimer 4 torsion A2 117 237 120 0.493
ONNO NO dimer 6 B2 429 664 235 0.646
ONONO Nitrosyl nitrite 9 B2 380 289 -91 1.317