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 QCISD/6-31G
Calculated values were scaled by 0.9636.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 332 132 0.602
C2H4+ Ethylene cation 4 Au 84 -313 -397 -0.269
C2H2 Acetylene 4 Πg 612 422 -190 1.451
CH3SH+ Methanethiol cation 8 A' 687 539 -148 1.276
CHONH2 formamide 12 A" 289 441 153 0.654
HNCO Isocyanic acid 4 A' 777 616 -161 1.261
HNCO Isocyanic acid 6 A" 656 503 -154 1.306
CBr2F2 Methane, dibromodifluoro- 3 A1 140 298 158 0.470
C3F8 perfluoropropane 13 A2 276 212 -64 1.305
CH3COOCH3 methyl acetate 27 A" 110 78 -32 1.408
CF2CCl2 difluorodichloroethylene 7 B1 1327 538 -789 2.464
CF2CCl2 difluorodichloroethylene 8 B1 989 307 -682 3.218
CF2CCl2 difluorodichloroethylene 11 B2 564 419 -145 1.347
CF2CCl2 difluorodichloroethylene 12 B2 323 175 -148 1.845
C9H8 Indene 40 A" 690 535 -155 1.290
C6H4O2 parabenzoquinone 16 B2g 794 627 -167 1.266
C6H4O2 parabenzoquinone 30 B3u 109 85 -24 1.282
CHCCH2CH3 1-Butyne 15 A' 197 156 -40 1.256
C3H6O 2-Propen-1-ol 24 A 188 94 -94 1.997
C3H2N2 Malononitrile 6 A1 167 130 -37 1.286
C4H9N Pyrrolidine 36 A" 65 22 -43 2.971
CO2 Carbon dioxide 3 Πu 667 516 -151 1.293
C5H8 Cyclopentene 18 A' 254 104 -150 2.438
C8H8 cubane 8 Eu 617 465 -152 1.328
CH2N4 1H-Tetrazole 11 A' 925 738 -187 1.253
C2H4O3 trioxolane124 21 B 193 148 -45 1.304
C2H2N4 sym-tetrazine 13 B2u 883 614 -269 1.439
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 514 163 0.683
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 310 -899 3.894
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 365 -168 1.460
HOCN cyanic acid 5 A' 460 315 -145 1.462
C4H6O2 2,3-Butanedione 21 Bg 240 115 -125 2.079
C4H2 Diacetylene 7 Πg 482 -777 -1259 -0.620
C4H2 Diacetylene 8 Πu 630 487 -143 1.292
C4H2 Diacetylene 9 Πu 231 117 -114 1.979
C2N2 Cyanogen 4 Πg 503 399 -104 1.260
C2N2 Cyanogen 5 Πu 234 182 -52 1.288
C6H5F Fluorobenzene 18 B1 685 525 -160 1.305
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C2H3NO3 Oxamic acid 16 A" 984 727 -257 1.353
C2H3NO3 Oxamic acid 17 A" 815 621 -194 1.311
C2H3NO3 Oxamic acid 18 A" 745 580 -165 1.283
C2H3NO3 Oxamic acid 21 A" 162 59 -103 2.727
C3H6O Oxetane 7 A1 1018 805 -213 1.264
C3H6O Oxetane 18 B1 90 -41 -131 -2.194
C3H6O Oxetane 23 B2 1228 926 -302 1.326
HCNO fulminic acid 3 Σ 1254 994 -260 1.262
HCNO fulminic acid 4 Π 537 424 -113 1.267
HCNO fulminic acid 5 Π 224 -122 -346 -1.835
C6H4F2 1,4-difluorobenzene 16 B2g 692 504 -188 1.373
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C5H8 1,4-Pentadiene 17 A 102 80 -22 1.276
CH3SSCH3 Disulfide, dimethyl 10 A 509 384 -125 1.325
CH3SSCH3 Disulfide, dimethyl 11 A 240 189 -51 1.271
CH3SSCH3 Disulfide, dimethyl 13 A 117 72 -45 1.614
CH3SSCH3 Disulfide, dimethyl 23 B 274 216 -58 1.269
C6H8 1,4-Cyclohexadiene 19 B1u 108 74 -34 1.456
C4H2N2 Fumaronitrile 12 Bg 383 298 -85 1.287
C4H6O Cyclobutanone 13 A2 909 699 -210 1.300
GeO2 Germanium dioxide 3 Πu 196 102 -94 1.920
SiF2+ Silicon difluoride cation 2 A1 350 248 -102 1.414
FCN Cyanogen fluoride 3 Π 451 316 -135 1.428
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.662
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 334 -122 1.367
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 98 -73 1.744
CCl2 dichloromethylene 1 A1 730 554 -176 1.318
CCl2 dichloromethylene 2 A1 335 261 -75 1.286
CCl2 dichloromethylene 3 B2 758 545 -213 1.390
FCO+ Carbonyl fluoride cation 3 Π 650 436 -214 1.491
CH3 Methyl radical 2 A2" 606 483 -124 1.257
SF6 Sulfur Hexafluoride 1 A1g 774 589 -184 1.313
SF6 Sulfur Hexafluoride 4 T1u 616 395 -220 1.558
SF6 Sulfur Hexafluoride 5 T2g 525 332 -193 1.580
SF6 Sulfur Hexafluoride 6 T2u 347 218 -129 1.589
CH2OH Hydroxymethyl radical 9 A 234 410 176 0.570
ClCO carbonyl monochloride 2 A' 570 71 -499 7.985
ClCO carbonyl monochloride 3 A' 335 70 -265 4.783
SO2F2 Sulfuryl fluoride 1 A1 1269 840 -429 1.511
SO2F2 Sulfuryl fluoride 2 A1 848 620 -228 1.367
SO2F2 Sulfuryl fluoride 3 A1 544 333 -211 1.631
SO2F2 Sulfuryl fluoride 4 A1 385 229 -156 1.684
SO2F2 Sulfuryl fluoride 5 A2 388 223 -165 1.740
SO2F2 Sulfuryl fluoride 7 B1 539 298 -241 1.807
SO2F2 Sulfuryl fluoride 8 B2 1502 925 -577 1.624
SO2F2 Sulfuryl fluoride 9 B2 553 332 -221 1.664
HCCF Fluoroacetylene 5 Π 367 216 -151 1.697
CS carbon monosulfide 1 Σ 1285 1020 -265 1.260
HO2 Hydroperoxy radical 3 A' 1098 841 -257 1.305
C6H6 Trimethylenecycopropane 10 A2" 212 166 -46 1.280
C6H6 Trimethylenecycopropane 20 E" 340 232 -108 1.463
OH- hydroxide anion 1 Σ 3738 2985 -753 1.252
CCl+ carbon monochloride cation 1 Σ 1175 751 -424 1.564
SeO2 Selenium dioxide 1 A1 922 702 -220 1.313
SeO2 Selenium dioxide 2 A1 373 294 -78 1.266
SeO2 Selenium dioxide 3 B2 966 616 -350 1.568
SO2 Sulfur dioxide 1 A1 1151 761 -391 1.513
SO2 Sulfur dioxide 2 A1 518 351 -167 1.474
SO2 Sulfur dioxide 3 B2 1362 615 -747 2.214
SeS- selenium monosulfide anion 1 Σ 469 352 -117 1.332
NH3 Ammonia 2 A1 950 742 -208 1.280
H2O2 Hydrogen peroxide 4 A 371 135 -236 2.739
H2O Water 1 A1 3657 2349 -1308 1.557
H2O Water 3 B2 3756 2474 -1282 1.518
CuCl Copper monochloride 1 Σ 418 265 -153 1.578
Cl2 Chlorine diatomic 1 Σg 560 386 -174 1.449
HN3 hydrogen azide 6 A" 607 456 -151 1.332
MgF2 Magnesium fluoride 3 Πu 165 115 -50 1.435
F2SO Thionyl Fluoride 1 A' 1335 854 -481 1.563
F2SO Thionyl Fluoride 3 A' 530 346 -185 1.535
F2SO Thionyl Fluoride 4 A' 378 226 -152 1.674
F2SO Thionyl Fluoride 6 A" 393 253 -139 1.548
FOOF Perfluoroperoxide 1 A 1210 730 -480 1.657
FOOF Perfluoroperoxide 4 A 202 153 -49 1.317
SF4 Sulfur tetrafluoride 1 A1 892 700 -192 1.274
SF4 Sulfur tetrafluoride 3 A1 532 387 -145 1.375
SF4 Sulfur tetrafluoride 4 A1 228 94 -134 2.422
SeF6 Selenium hexafluoride 4 T1u 437 349 -88 1.253
SeF6 Selenium hexafluoride 5 T2g 405 317 -88 1.277
SeF6 Selenium hexafluoride 6 T2u 264 202 -62 1.305
BeCl2 Beryllium chloride 3 Πu 238 191 -47 1.246
BrF3 Bromine trifluoride 1 A1 675 534 -141 1.265
BrF5 bromine pentafluoride 1 A1 683 519 -164 1.315
BrF5 bromine pentafluoride 2 A1 587 444 -143 1.321
BrF5 bromine pentafluoride 3 A1 369 288 -81 1.282
BrF5 bromine pentafluoride 4 B1 312 228 -84 1.370
BrF5 bromine pentafluoride 6 B2 281 186 -95 1.512
BrF5 bromine pentafluoride 8 E 415 317 -98 1.310
BrF5 bromine pentafluoride 9 E 237 168 -69 1.410
ClF3 Chlorine trifluoride 1 A1 752 546 -206 1.378
ClF3 Chlorine trifluoride 2 A1 529 376 -153 1.406
ClF3 Chlorine trifluoride 3 A1 328 178 -150 1.846
ClF3 Chlorine trifluoride 4 B1 328 218 -110 1.508
ClF3 Chlorine trifluoride 6 B2 442 267 -175 1.655
ZnCN Zinc monocyanide 3 Π 212 141 -71 1.501
GeCl Germanium monochloride 1 Σ 408 317 -91 1.288
N2O Nitrous oxide 2 Σ 1298 1017 -281 1.276
N2O Nitrous oxide 3 Π 596 327 -270 1.826
S2Cl2 Disulfur dichloride 1 A 546 372 -174 1.468
S2Cl2 Disulfur dichloride 2 A 466 358 -108 1.303
S2Cl2 Disulfur dichloride 3 A 202 140 -62 1.444
S2Cl2 Disulfur dichloride 4 A 95 65 -30 1.453
S2Cl2 Disulfur dichloride 5 B 461 361 -100 1.278
S2Cl2 Disulfur dichloride 6 B 244 169 -75 1.446
NCl3 nitrogen trichloride 2 A1 349 265 -84 1.319
NCl3 nitrogen trichloride 3 E 642 512 -130 1.255
NCl3 nitrogen trichloride 4 E 257 198 -59 1.296
GeCl2 Germanium dichloride 1 A1 409 324 -85 1.264
NO2 Nitrogen dioxide 3 B2 1618 1234 -384 1.311
S8 Octasulfur 1 A1 475 350 -125 1.357
S8 Octasulfur 2 A1 218 155 -63 1.406
S8 Octasulfur 3 B1 411 322 -89 1.277
S8 Octasulfur 4 B2 243 180 -63 1.351
S8 Octasulfur 5 E1 471 349 -122 1.350
S8 Octasulfur 6 E1 191 140 -51 1.363
S8 Octasulfur 7 E2 475 362 -113 1.314
S8 Octasulfur 8 E2 152 111 -41 1.368
S8 Octasulfur 10 E3 437 342 -95 1.279
S8 Octasulfur 11 E3 248 177 -71 1.397
N2O3 Dinitrogen trioxide 9 A" 63 134 71 0.471
SCl2 Sulfur dichloride 1 A1 525 376 -149 1.397
SCl2 Sulfur dichloride 2 A1 208 141 -67 1.476
SCl2 Sulfur dichloride 3 B2 535 387 -148 1.384
SF5 Sulfur pentafluoride 2 A1 633 493 -140 1.285
SF5 Sulfur pentafluoride 3 A1 554 312 -241 1.773
SF5 Sulfur pentafluoride 8 E 525 305 -220 1.721
SF5 Sulfur pentafluoride 9 E 387 195 -193 1.990
NS Mononitrogen monosulfide 1 Σ 1219 905 -313 1.346
NS+ nitrogen sulfide cation 1 Σ 1415 1072 -343 1.320
C3 carbon trimer 3 Πu 63 -192 -255 -0.331
SiP Silicon monophosphide 1 Σ 616 462 -154 1.332
CaOH Calcium monohydroxide 2 Σ 353 586 233 0.603
Se2 Selenium diatomic 1 Σg 385 298 -87 1.292
PS phosphorus sulfide 1 Σ 739 498 -241 1.484
PS+ phosphorus monosulfide cation 1 Σ 845 609 -236 1.388
S3- Sulfur trimer anion 3 B2 594 427 -168 1.393
S3 Sulfur trimer 1 A1 581 421 -160 1.381
S3 Sulfur trimer 2 A1 281 181 -100 1.552
S3 Sulfur trimer 3 B2 680 287 -393 2.371
H2S2 Disulfane 3 A 515 379 -136 1.359
H2S2 Disulfane 4 A 417 315 -103 1.327
CuF Copper monofluoride 1 Σ 623 383 -239 1.624
AlCl Aluminum monochloride 1 Σ 482 377 -105 1.279
SiS2 Silicon disulfide 1 Σg 514 398 -116 1.291
SiH- silicon monohydride anion 1 Σ 2175 1585 -590 1.372
SF5Cl sulfur chloropentafluoride 2 A1 707 561 -146 1.261
SF5Cl sulfur chloropentafluoride 3 A1 602 422 -180 1.428
SF5Cl sulfur chloropentafluoride 4 A1 402 265 -137 1.515
SF5Cl sulfur chloropentafluoride 5 B1 625 317 -308 1.971
SF5Cl sulfur chloropentafluoride 7 B2 505 214 -291 2.364
SF5Cl sulfur chloropentafluoride 9 E 579 370 -209 1.565
SF5Cl sulfur chloropentafluoride 10 E 441 271 -170 1.629
SF5Cl sulfur chloropentafluoride 11 E 397 164 -233 2.426
SF2 sulfur difluoride 2 A1 355 254 -101 1.400
SO Sulfur monoxide 1 Σ 1151 596 -555 1.931
SO+ sulfur monoxide cation 1 Σ 1360 937 -423 1.451
SO Sulfur monoxide 1 Σ 1069 814 -254 1.312
BrCl Bromine monochloride 1 Σ 444 321 -123 1.382
NBr nitrogen monobromide 1 Σ 692 490 -202 1.412
H3O+ hydronium cation 2 A1 954 494 -461 1.933
ZnH2 Zinc hydride 3 Πu 633 465 -167 1.360
PO- phosphorus monoxide anion 1 Σ 1000 783 -217 1.278
PO Phosphorus monoxide 1 Σ 1233 925 -308 1.333
PO+ phosphorus monoxide cation 1 Σ 1405 982 -423 1.430
HS2 Thiosulfeno radical 3 A' 596 396 -201 1.507
ClONO2 Chlorine nitrate 7 A' 273 207 -66 1.321
ClONO2 Chlorine nitrate 9 A" 124 91 -33 1.357
SCl sulfur monochloride 1 Σ 577 408 -169 1.413
CaCl calcium monochloride 1 Σ 368 291 -76 1.263
BrO Bromine monoxide 1 Σ 726 559 -167 1.298
SCN thiocyanato radical 2 Σ 762 599 -162 1.271
PF+ phosphorus monofluoride cation 1 Σ 1053 786 -267 1.340
SF Monosulfur monofluoride 1 Σ 838 655 -182 1.278
CHBr bromomethylene 3 A' 676 498 -179 1.359
AsCl Arsenic monochloride 1 Σ 443 308 -135 1.440
BBr Boron monobromide 1 Σ 684 523 -161 1.307
H2POH Phosphinous acid 9 A" 375 224 -152 1.678
Mg2 Magnesium diatomic 1 Σg 51 12 -39 4.278
ZnCH3 Zinc monomethyl 6 E 315 616 301 0.511
NNS Nitrogen sulfide 2 Σ 752 520 -232 1.445
ClONO chlorine nitrite 5 A' 270 192 -78 1.403
CH3BO Borane, methyloxo- 7 E 897 1462 566 0.613
ONONO Nitrosyl nitrite 6 B1 140 103 -37 1.362