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III.G.1.a.

Comparison of levels of theory for As-N


Click on an entry for a histogram of the values.
The subscript refers to how many bonds of that type have been calculated.
average calculated bond lengths (Å)
Methods with predefined basis sets
semi-empirical PM3 1.5861
1
PM6 1.3703
1
composite G2 1.5313
1
G3 1.5301
1
G3B3 1.6056
1
CBS-Q 1.5326
1

average calculated bond lengths (Å)
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
hartree fock HF 1.5133
1
1.6091
1
1.6016
1
1.6033
1
1.5749
1
1.5750
1
1.5690
1
1.5691
1
1.5691
1
1.5720
1
1.5718
1
1.5741
1
1.5715
1
1.5694
1
1.5777
1
1.5721
1
1.5695
1
density functional LSDA 1.5416
1
1.6467
1
1.6467
1
1.6486
1
1.6174
1
1.6174
1
1.6083
1
1.6093
1
1.6093
1
1.6112
1
1.6105
1
1.6193
1
1.6088
1
  1.6187
1
1.6085
1
 
SVWN   1.6489
1
    1.6174
1
1.6174
1
1.6083
1
1.6093
1
1.6093
1
1.6112
1
  1.6193
1
1.6088
1
  1.6187
1
1.6085
1
 
BLYP 1.5600
1
1.6720
1
1.6719
1
1.6741
1
1.6413
1
1.6413
1
1.6320
1
1.6352
1
1.6352
1
1.6343
1
1.6369
1
1.6445
1
1.6341
1
       
B1B95 1.5452
1
1.6349
1
1.6349
1
1.6373
1
1.6069
1
1.6069
1
1.5988
1
1.6007
1
1.6007
1
1.6019
1
1.6021
1
1.6076
1
1.6005
1
  1.6085
1
1.6007
1
 
B3LYP 1.5460
1
1.6500
1
1.6472
1
1.6490
1
1.6180
1
1.6180
1
1.6098
1
1.6116
1
1.6116
1
1.6123
1
1.6135
1
1.6196
1
1.6115
1
1.6092
1
1.6202
1
1.6117
1
1.6091
1
B3LYPultrafine         1.6182
1
            1.6198
1
1.6117
1
  1.6204
1
1.6119
1
 
B3PW91 1.5481
1
1.6476
1
1.6435
1
1.6445
1
1.6136
1
1.6136
1
1.6051
1
1.6071
1
1.6071
1
1.6083
1
1.6086
1
1.6147
1
1.6070
1
       
mPW1PW91 1.5449
1
1.6433
1
1.6386
1
1.6396
1
1.6090
1
1.6090
1
1.6008
1
1.6027
1
1.6027
1
1.6039
1
1.6042
1
1.6098
1
1.6028
1
  1.6107
1
1.6029
1
 
M06-2X 1.5334
1
1.6380
1
1.6333
1
1.6320
1
1.6032
1
1.6032
1
1.5958
1
1.5998
1
1.5998
1
1.5999
1
1.6019
1
1.6037
1
1.6008
1
  1.6058
1
1.6010
1
 
PBEPBE 1.5604
1
1.6685
1
1.6664
1
1.6673
1
1.6344
1
1.6344
1
1.6250
1
1.6284
1
1.6284
1
1.6277
1
1.6299
1
1.6369
1
1.6272
1
  1.6365
1
1.6273
1
 
PBEPBEultrafine         1.6346
1
            1.6370
1
1.6275
1
  1.6367
1
1.6276
1
 
PBE1PBE 1.5446
1
1.6396
1
1.6396
1
1.6405
1
1.6096
1
1.6096
1
1.6015
1
1.6033
1
1.6033
1
1.6044
1
1.6050
1
1.6104
1
1.6034
1
  1.6113
1
1.6036
1
 
HSEh1PBE 1.5445
1
1.6448
1
1.6406
1
1.6417
1
1.6107
1
1.6107
1
1.6025
1
1.6043
1
1.6043
1
1.6054
1
1.6061
1
1.6116
1
1.6045
1
  1.6124
1
1.6047
1
 
TPSSh         1.6200
1
  1.6083
1
          1.6111
1
       
Moller Plesset perturbation MP2 1.7143
1
1.7628
1
1.7454
1
1.7708
1
1.6858
1
1.6858
1
1.6719
1
1.6772
1
1.6772
1
1.6693
1
1.6709
1
1.6888
1
1.6629
1
1.6528
1
1.6892
1
1.6633
1
1.6512
1
MP2=FULL 1.7132
1
1.7619
1
1.7452
1
1.7684
1
1.6805
1
1.6805
1
1.6669
1
1.6681
1
1.6681
1
1.6566
1
1.6719
1
1.6878
1
1.6573
1
1.6441
1
1.6872
1
1.6530
1
1.6398
1
MP3         1.6058
1
  1.5978
1
                   
MP3=FULL         1.5927
1
  1.5809
1
                   
MP4   1.7885
1
    1.7036
1
      1.7012
1
  1.7026
1
1.7091
1
1.6884
1
  1.7147
1
1.6882
1
 
MP4=FULL   1.7867
1
    1.6984
1
      1.6951
1
    1.7073
1
1.6806
1
  1.7114
1
1.6750
1
 
Configuration interaction CID   1.6531
1
1.6437
1
1.6488
1
1.6113
1
    1.6014
1
                 
CISD   1.6561
1
1.6466
1
1.6523
1
1.6143
1
    1.6047
1
                 
Quadratic configuration interaction QCISD   1.6793
1
1.6705
1
1.6770
1
1.6342
1
1.6342
1
1.6254
1
1.6246
1
1.6246
1
1.6236
1
1.6213
1
1.6328
1
1.6163
1
  1.6350
1
1.6159
1
 
QCISD(T)         1.6479
1
          1.6354
1
1.6473
1
1.6310
1
  1.6500
1
1.6308
1
 
Coupled Cluster CCD   1.6723
1
1.6629
1
1.6685
1
1.6270
1
1.6270
1
1.6182
1
1.6166
1
1.6166
1
1.6167
1
1.6131
1
1.6252
1
1.6088
1
  1.6277
1
1.6088
1
 
CCSD         1.6312
1
          1.6181
1
1.6297
1
1.6135
1
1.6048
1
1.6320
1
1.6132
1
1.6035
1
CCSD=FULL         1.6273
1
          1.6185
1
1.6291
1
1.6095
1
1.5990
1
1.6308
1
1.6064
1
 
CCSD(T)         1.6466
1
          1.6341
1
1.6459
1
1.6296
1
1.6209
1
1.6493
1
1.6296
1
1.6197
1
CCSD(T)=FULL         1.6427
1
          1.6348
1
1.6453
1
1.6254
1
1.6148
1
1.6477
1
1.6223
1
1.6114
1

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.5994
1
  1.5990
1
  1.6109
1
1.6030
1
density functional B3LYP 1.6508
1
  1.6490
1
  1.6604
1
1.6500
1
Moller Plesset perturbation MP2 1.7889
1
  1.7914
1
  1.8044
1
1.7838
1
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.