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XIII.F.2. (III.B.7.b.) (IV.C.7.) (XVIII.B.2.)

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/3-21G*
Calculated values were scaled by 0.9026.

Species Name mode Symmetry Experiment Theory difference ratio
NH2CONH2 Urea 17 B2 1004 3426 2422 0.293
NH2CONH2 Urea 18 B2 543 994 451 0.546
NH2CONH2 Urea 16 B2 1393 3540 2147 0.393
CH3CONH2 Acetamide 20 A 259 404 145 0.641
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.211
CH3NH2 methyl amine 14 A" 1195 945 -250 1.264
CHONH2 formamide 12 A" 289 495 206 0.584
CH3NO2 Methane, nitro- 11 A" 1583 3021 1438 0.524
CBr2F2 Methane, dibromodifluoro- 3 A1 140 331 191 0.423
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 517 -115 1.222
CH3COCH2CH3 2-Butanone 33 A" 87 51 -36 1.710
C3H6O 2-Propen-1-ol 22 A 377 308 -70 1.226
C3H6O 2-Propen-1-ol 24 A 188 93 -95 2.016
C3H6O 2-Propen-1-ol 21 A 554 449 -106 1.235
C2H2O2 Ethanedial 7 Au 127 189 62 0.671
C5H12 Pentane 23 A2 131 105 -26 1.243
C4H8O Furan, tetrahydro- 17 A 286 237 -49 1.205
C4H8O Furan, tetrahydro- 33 B 137 82 -55 1.680
C3H6O3 1,3,5-Trioxane 7 A1 476 378 -98 1.259
C3H6O3 1,3,5-Trioxane 20 E 307 243 -64 1.265
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 159 -34 1.212
C4H8O2 1,4-Dioxane 19 Au 288 219 -69 1.314
C5H8 Cyclopentene 18 A' 254 114 -140 2.221
C4H8 cyclobutane 6 A1 199 153 -46 1.303
CH2NN diazomethane 6 B1 406 580 174 0.700
C4H6O2 2,3-Butanedione 21 Bg 240 99 -141 2.414
C4H6O2 2,3-Butanedione 16 Au 48 70 22 0.681
C2N2 Cyanogen 4 Πg 503 728 225 0.691
C2H3NO3 Oxamic acid 18 A" 745 605 -140 1.231
C2H3NO3 Oxamic acid 15 A' 328 266 -62 1.233
C2H3NO3 Oxamic acid 17 A" 815 679 -136 1.200
C2H3NO3 Oxamic acid 21 A" 162 102 -60 1.588
C2H3NO3 Oxamic acid 3 A' 2600 3413 813 0.762
C3H6O Oxetane 23 B2 1228 974 -254 1.261
C3H6O Oxetane 7 A1 1018 844 -174 1.206
C3O2 Carbon suboxide 7 Πu 61 139 78 0.440
HCNO fulminic acid 3 Σ 1254 726 -528 1.727
HCNO fulminic acid 4 Π 537 796 258 0.675
HCNO fulminic acid 5 Π 224 480 256 0.467
Zn(CH3)2 dimethyl zinc 11 E' 134 -52 -186 -2.571
C6H12 2-Butene, 2,3-dimethyl- 12 Au 182 151 -31 1.204
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 329 148 0.550
C5H8 1,4-Pentadiene 33 B 331 91 -240 3.641
C5H8 1,4-Pentadiene 17 A 102 82 -20 1.248
C5H8 1,4-Pentadiene 16 A 137 303 166 0.452
C6H10 1,5-Hexadiene 29 Bg 264 153 -111 1.725
C6H10 1,5-Hexadiene 14 Ag 351 264 -87 1.328
COBr2 Carbonic dibromide 6 B2 512 351 -161 1.457
COBr2 Carbonic dibromide 4 B1 757 524 -233 1.443
CH3SSCH3 Disulfide, dimethyl 13 A 117 97 -20 1.201
C2F2 difluoroacetylene 4 Πg 270 460 190 0.587
C3H7N Cyclopropylamine 12 A' 989 790 -199 1.251
C4H6 Cyclobutene 7 A1 1113 925 -188 1.204
C4N2 2-Butynedinitrile 6 Πg 504 889 385 0.567
CaO Calcium monoxide 1 Σ 732 505 -227 1.449
LiOH lithium hydroxide 3 Π 257 421 164 0.609
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 224 80 0.644
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 116 -55 1.475
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 360 -96 1.268
C5H8 1,3-Pentadiene, (E)- 32 A" 129 188 59 0.687
C5H8 1,3-Pentadiene, (E)- 31 A" 361 244 -117 1.477
C2H5 Ethyl radical 9 A' 528 395 -133 1.337
CN Cyano radical 1 Σ 2069 1638 -431 1.263
C2H+ Ethynyl cation 3 Π 550 853 304 0.644
CH3OO methylperoxy radical 7 A' 902 689 -213 1.310
CH3 Methyl radical 2 A2" 606 382 -224 1.586
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 89 -269 4.001
C6H8 1,3,5-Hexatriene, (Z)- 36 B2 243 356 113 0.682
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 847 -289 1.341
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 127 -137 2.076
C6H6 2,4-Hexadiyne 14 E' 353 520 167 0.679
HO2 Hydroperoxy radical 3 A' 1098 760 -337 1.443
OH- hydroxide anion 1 Σ 3738 2636 -1103 1.418
OH Hydroxyl radical 1 Σ 3738 3255 -483 1.148
OH+ hydoxyl cation 1 Σ 3113 2627 -486 1.185
CCl carbon monochloride 1 Σ 877 673 -204 1.303
CH2CHO Vinyloxy radical 11 A" 557 814 257 0.684
C2Cl2 dichloroacetylene 4 Πg 333 595 262 0.560
C2Cl2+ dichloroacetylene cation 4 Πg 318 540 222 0.589
BF3+ boron trifluoride cation 4 E' 411 342 -69 1.202
HF Hydrogen fluoride 1 Σ 4138 3664 -475 1.130
NH3 Ammonia 2 A1 950 772 -178 1.231
HNO2 Nitrous acid 6 A" 543 448 -95 1.212
HN3 hydrogen azide 4 A' 1151 832 -318 1.382
AsH3+ Arsine cation 2 A1 452 717 265 0.630
FNO3 Fluorine nitrate 9 A" 152 110 -42 1.376
FNO3 Fluorine nitrate 1 A' 1759 1345 -414 1.308
N2O Nitrous oxide 2 Σ 1285 739 -546 1.738
N2O Nitrous oxide 3 Π 589 481 -108 1.224
PCl5 Phosphorus pentachloride 2 A1' 370 257 -113 1.440
PCl5 Phosphorus pentachloride 3 A2" 465 379 -86 1.227
O3 Ozone 2 A1 705 558 -147 1.263
O3 Ozone 3 B2 1042 711 -331 1.466
NO Nitric oxide 1 Σ 1904 679 -1225 2.803
NO2 Nitrogen dioxide 3 B2 1618 1132 -486 1.429
N2O4 Dinitrogen tetroxide 10 B3g 1718 1376 -342 1.248
N2O4 Dinitrogen tetroxide 3 Ag 265 392 127 0.676
N2O4 Dinitrogen tetroxide 8 B2u 1757 1397 -360 1.258
N2O3 Dinitrogen trioxide 2 A' 1652 1357 -295 1.217
N2O3 Dinitrogen trioxide 9 A" 63 144 81 0.438
N2O3 Dinitrogen trioxide 6 A' 241 378 137 0.638
NS Mononitrogen monosulfide 1 Σ 1219 731 -488 1.668
SiN Silicon nitride 1 Σ 1151 761 -390 1.513
FO Oxygen monofluoride 1 Σ 1053 109 -944 9.636
CaOH Calcium monohydroxide 2 Σ 353 621 268 0.568
Cu2 Copper dimer 1 Σg 265 161 -103 1.639
NCl nitrogen monochloride 1 Σ 828 488 -340 1.697
PS phosphorus sulfide 1 Σ 739 506 -233 1.459
S3- Sulfur trimer anion 3 B2 594 476 -118 1.247
ClNO2 Nitryl chloride 5 B2 1684 1234 -450 1.364
ND3 Ammonia-d3 2 A1 748 590 -158 1.268
NH2- amino anion 3 B2 3190 2608 -582 1.223
NH2- amino anion 1 A1 3122 2613 -509 1.195
NH Imidogen 1 Σ 3283 2854 -428 1.150
SiH- silicon monohydride anion 1 Σ 2175 1779 -396 1.223
H3O+ hydronium 2 A1 954 513 -441 1.860
ZnH2 Zinc hydride 3 Πu 633 271 -361 2.333
ZnH2 Zinc hydride 2 Σu 1889 1464 -426 1.291
PO Phosphorus monoxide 1 Σ 1233 713 -520 1.730
AlO Aluminum monoxide 1 Σ 979 804 -175 1.218
ClONO2 Chlorine nitrate 1 A' 1737 1317 -420 1.319
ClONO2 Chlorine nitrate 9 A" 124 97 -26 1.271
ClO Monochlorine monoxide 1 Σ 854 552 -302 1.546
CaCl calcium monochloride 1 Σ 368 299 -69 1.229
BrO Bromine monoxide 1 Σ 726 291 -435 2.498
PN+ phosphorus nitride cation 1 Σ 1200 608 -592 1.975
GeH2 germylene 2 A1 916 1827 911 0.501
GeH2 germylene 1 A1 1856 914 -942 2.030
Mg2 Magnesium diatomic 1 Σg 51 344 293 0.149
ClS2 Sulfur chloride 1 A' 662 544 -118 1.216
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.531
BrONO Bromine nitrite 6 A" 150 118 -32 1.276