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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 MP2=FULL/cc-pV(T+d)Z
Calculated values were scaled by 0.9481.

Species Name mode int rot Symmetry Experiment Theory difference ratio
HCN+ hydrogen cyanide cation 1 Σ 3050 3511 461 0.869
HCN+ hydrogen cyanide cation 2 Σ 1800 2699 899 0.667
CH2Cl2 Methylene chloride 1 A1 2999 276 -2723 10.847
CH2Cl2 Methylene chloride 2 A1 1467 709 -758 2.070
CH2Cl2 Methylene chloride 3 A1 717 1417 700 0.506
CH2Cl2 Methylene chloride 4 A1 282 3011 2729 0.094
CH2Cl2 Methylene chloride 6 B1 3040 872 -2168 3.488
CH2Cl2 Methylene chloride 7 B1 898 3068 2170 0.293
CH2Cl2 Methylene chloride 8 B2 1268 763 -505 1.661
CH2Cl2 Methylene chloride 9 B2 758 1241 483 0.611
CH3COOCH3 methyl acetate 27 torsion A" 110 66 -44 1.675
C4H9N Pyrrolidine 36 A" 65 49 -16 1.335
C5H8 Cyclopentene 18 torsion A' 254 179 -75 1.416
CH2NN diazomethane 6 B1 406 227 -179 1.788
C2H3NO3 Oxamic acid 3 A' 2600 3454 854 0.753
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.423
C5H8 1,4-Pentadiene 16 A 137 292 155 0.469
CO+ carbon monoxide cation 1 Σ 2184 2727 544 0.801
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 347 -109 1.314
CN Cyano radical 1 Σ 2042 2757 715 0.741
C2H Ethynyl radical 2 Σ 1841 2403 562 0.766
C2H Ethynyl radical 3 torsion Π 372 778 407 0.477
CH3OO methylperoxy radical 12 torsion A" 170 122 -48 1.394
O2+ diatomic oxygen cation 1 Σg 1873 1445 -428 1.296
OClO Chlorine dioxide 3 B2 1110 2315 1205 0.479
N2O3 Dinitrogen trioxide 9 torsion A" 63 161 98 0.391
C3 carbon trimer 3 Πu 63 179 115 0.355
SiP Silicon monophosphide 1 Σ 611 1055 444 0.579
AlO Aluminum monoxide 1 Σ 965 399 -566 2.420
SCN thiocyanato radical 1 Σ 1942 2372 430 0.819
ClOO chloroperoxy radical 2 A' 414 1052 639 0.393
ClOO chloroperoxy radical 3 A' 201 475 274 0.424
OPCl Phosphorus oxychloride 2 A' 308 491 183 0.627
OPCl Phosphorus oxychloride 3 A' 492 294 -198 1.675
H2POH Phosphinous acid 9 A" 375 257 -118 1.460
SNO Nitrogen oxide sulfide 3 A' 792 507 -285 1.562