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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 MP2FC/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
CH3COOH Acetic acid 18 A" 93 76 -17 1.226
CH3OH Methyl alcohol 12 A" 200 299 99 0.668
CH3COCH3 Acetone 12 A2 77 20 -57 3.834
C2H2 Acetylene 4 Πg 612 392 -220 1.563
CH3NH2 methyl amine 14 A" 1195 931 -264 1.284
HCN+ hydrogen cyanide cation 2 Σ 1800 2789 989 0.645
HCN+ hydrogen cyanide cation 1 Σ 3050 3784 734 0.806
CH3CCH propyne 10 E 328 254 -74 1.292
CHONH2 formamide 12 A" 289 167 -121 1.725
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
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.753
C3H6O 2-Propen-1-ol 21 A 554 422 -132 1.314
C3H2N2 Malononitrile 6 A1 167 132 -35 1.261
C4H8O Furan, tetrahydro- 33 B 137 53 -84 2.586
NH2CN cyanamide 5 A' 408 644 236 0.634
C4H6O2 2,3-Butanedione 13 Au 1111 910 -201 1.221
C4H6O2 2,3-Butanedione 21 Bg 240 125 -115 1.922
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.223
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 17 A" 815 643 -172 1.267
C2H3NO3 Oxamic acid 16 A" 984 789 -195 1.248
C2H3NO3 Oxamic acid 18 A" 745 606 -139 1.229
C2H3NO3 Oxamic acid 21 A" 162 61 -101 2.657
C2H3NO3 Oxamic acid 3 A' 2600 3452 852 0.753
CH3CCCH3 2-Butyne 12 E' 213 176 -37 1.209
CH3CCCH3 2-Butyne 16 E" 371 210 -161 1.763
C5H8 1,4-Pentadiene 31 B 721 583 -138 1.237
C5H8 1,4-Pentadiene 33 B 331 98 -233 3.380
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.208
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
COBr2 Carbonic dibromide 6 B2 512 336 -176 1.522
COBr2 Carbonic dibromide 4 B1 757 490 -267 1.543
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.225
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
C3H6O2 1,3-Dioxolane 5 A 1480 2929 1449 0.505
C3H6O2 1,3-Dioxolane 4 A 1509 2961 1452 0.510
C3H6O2 1,3-Dioxolane 6 A 1361 2894 1533 0.470
C3H6O2 1,3-Dioxolane 13 A 658 1214 556 0.542
C2F2 difluoroacetylene 4 Πg 270 223 -47 1.212
C3H7N Cyclopropylamine 12 A' 989 809 -180 1.222
C4H6 Cyclobutene 13 A2 325 268 -57 1.214
HCCCN Cyanoacetylene 7 Π 222 167 -55 1.327
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.357
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 134 -37 1.277
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
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
CH3 Methyl radical 2 A2" 606 474 -132 1.278
SO2F2 Sulfuryl fluoride 4 A1 385 320 -65 1.202
SO2F2 Sulfuryl fluoride 9 B2 553 456 -97 1.213
SO2F2 Sulfuryl fluoride 5 A2 388 315 -73 1.232
CCl3 Trichloromethyl radical 2 A1 251 366 115 0.686
C4H6 Methylenecyclopropane 17 B1 360 252 -108 1.429
C2Cl2 dichloroacetylene 4 Πg 333 111 -222 2.987
C2Cl2+ dichloroacetylene cation 5 Πu 233 171 -62 1.365
O2+ diatomic oxygen cation 1 Σg 1906 1391 -515 1.370
AsH3+ Arsine cation 2 A1 452 685 233 0.659
ClF3 Chlorine trifluoride 3 A1 328 273 -55 1.202
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
N2O3 Dinitrogen trioxide 7 A' 205 170 -35 1.209
NS+ nitrogen sulfide cation 1 Σ 1415 1147 -268 1.233
PS phosphorus sulfide 1 Σ 739 1340 601 0.552
ClNO2 Nitryl chloride 3 A1 364 302 -62 1.206
SiH- silicon monohydride anion 1 Σ 2175 1799 -376 1.209
SO+ sulfur monoxide cation 1 Σ 1360 1133 -227 1.201
PO Phosphorus monoxide 1 Σ 1233 6882 5648 0.179
PO+ phosphorus monoxide cation 1 Σ 1405 1146 -259 1.226
AlO Aluminum monoxide 1 Σ 979 626 -353 1.564
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
PN Phosphorus mononitride 1 Σ 1337 1071 -266 1.249
NCO isocyanato radical 1 Σ 1921 2375 454 0.809
GeH2 germylene 2 A1 916 1901 985 0.482
GeH2 germylene 1 A1 1856 933 -923 1.990
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.908
BrONO Bromine nitrite 4 A' 391 293 -99 1.337