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III.G.1.a.

Comparison of levels of theory for S-Cl


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 AM1 1.9717
7
PM3 2.0352
17
PM6 2.0250
16
composite G2 2.0169
15
G3 2.0148
17
G3B3 2.0727
17
G4 2.0367
14
CBS-Q 2.0112
15

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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z aug-cc-pV(T+d)Z
hartree fock HF 2.1039
17
2.3397
17
2.0123
17
2.1994
16
2.0186
34
2.0148
17
2.0172
17
2.0278
17
2.0278
17
2.0088
17
2.0115
13
2.0339
17
2.0344
17
2.0130
17
1.9913
10
2.0339
17
2.0125
17
1.9781
7
2.0133
16
2.0109
4
ROHF   2.4467
2
2.0235
2
2.2234
1
2.0234
2
2.0234
2
2.0263
2
2.0378
2
2.0136
1
    2.0170
1
2.0439
2
2.0203
2
1.9882
1
2.0177
1
1.9948
1
1.9879
1
1.9855
1
1.9855
1
density functional LSDA 2.1638
17
2.1720
17
2.0424
17
2.2245
17
2.0486
17
2.0486
17
2.0497
17
2.0614
17
2.0614
17
2.0216
17
  2.0435
4
2.0567
17
2.0289
17
1.9880
2
2.0533
17
1.9923
7
1.9856
2
2.0058
4
2.0054
4
SVWN   2.2552
17
    2.0618
15
2.0357
4
2.0517
17
2.0455
4
2.0455
4
2.0146
4
    2.0414
4
2.0190
4
  2.0387
4
2.0185
4
  2.0058
4
2.0054
4
BLYP 2.2176
17
2.3324
16
2.1203
17
2.3019
16
2.1201
17
2.1202
17
2.1226
17
2.1387
17
2.1389
17
2.0838
15
  2.1111
4
2.1280
17
2.1004
17
  2.1462
7
    2.0716
4
2.0707
4
B1B95 2.1562
17
2.2045
17
2.0383
17
2.2199
17
2.0292
13
2.0422
17
2.0434
17
2.0542
17
2.0542
17
2.0215
17
  2.0400
4
2.0525
17
2.0237
17
1.9504
3
2.0468
17
1.9916
7
1.9488
3
2.0080
4
2.0076
4
B3LYP 2.1772
17
2.2852
17
2.0717
17
2.2506
17
2.0748
17
2.0748
17
2.0764
17
2.0897
17
2.0758
11
2.0529
17
2.0378
5
2.0873
17
2.0798
17
2.0593
17
2.0030
7
2.0806
15
2.0578
15
2.0020
7
2.0558
16
2.0392
4
B3LYPultrafine         2.0650
15
  2.1003
7
        2.0747
4
2.0716
4
2.0859
11
  2.0701
4
2.0332
13
  2.0397
4
2.0392
4
B3PW91 2.1466
11
2.2643
16
2.0494
17
2.2302
17
2.0528
17
2.0529
17
2.0540
17
2.0647
17
2.0524
11
2.0259
15
  2.0539
4
2.0632
17
2.0374
17
  2.0733
7
    2.0207
4
2.0203
4
mPW1PW91 2.1381
11
2.2568
17
2.0377
13
2.2193
17
2.0430
17
2.0430
17
2.0442
17
2.0543
17
2.0544
17
2.0235
17
  2.0463
4
2.0538
17
2.0280
15
  2.0608
10
2.0244
4
  2.0138
4
2.0135
4
M06-2X 2.1285
4
2.2313
4
2.0235
4
2.1958
4
2.0391
17
2.0339
4
2.0360
4
2.0439
4
2.0439
4
2.0212
4
  2.0435
4
2.0422
4
2.0228
4
  2.0421
4
2.0228
4
  2.0137
4
2.0135
4
PBEPBE 2.1684
11
2.2947
17
2.0636
11
2.2406
11
2.0741
15
2.0741
15
2.0752
15
2.0876
15
2.0967
17
2.0547
17
2.0593
7
2.0750
4
2.0827
17
2.0544
15
1.9784
3
2.0413
5
2.0653
13
1.9765
3
2.0378
4
2.0373
4
PBEPBEultrafine         2.1066
15
            2.0749
4
2.0720
4
2.0506
4
  2.0690
4
2.0501
4
  2.0378
4
2.0373
4
PBE1PBE 2.1425
4
2.0250
4
2.0250
4
2.2043
4
2.0404
17
2.0336
4
2.0356
4
2.0442
4
2.0442
4
2.0190
4
  2.0437
4
2.0414
4
2.0223
4
  2.0404
4
2.0221
4
  2.0119
4
2.0115
4
HSEh1PBE 2.1449
4
2.2478
4
2.0272
4
2.2081
4
2.0494
15
2.0358
4
2.0378
4
2.0467
4
2.0467
4
2.0209
4
  2.0460
4
2.0437
4
2.0242
4
  2.0425
4
2.0241
4
  2.0135
4
2.0132
4
TPSSh   2.2683
4
2.0479
4
2.2288
4
2.0534
14
2.0536
4
2.0539
14
2.0636
4
      2.0625
4
2.0605
4
2.0421
14
  2.0584
4
2.0384
4
  2.0275
4
2.0269
4
Moller Plesset perturbation MP2 2.1491
11
2.3084
16
2.0396
17
2.2811
17
2.0398
19
2.0411
17
2.0584
35
2.0545
17
2.0545
17
2.0188
15
  2.0560
17
2.0621
17
2.0266
17
1.9903
6
2.0676
15
1.9942
8
1.9894
6
2.0257
16
2.0141
4
MP2=FULL 2.1487
11
2.2818
15
2.0377
13
2.2640
13
2.0391
19
2.0403
17
2.0421
17
2.0536
17
2.0443
11
2.0088
11
  2.0471
4
2.0590
15
2.0203
15
1.9866
6
2.0720
13
1.9872
5
2.0179
4
2.0177
16
2.0034
4
ROMP2 2.0819
1
1.9914
1
1.9914
1
2.2178
1
2.0004
1
2.0004
1
2.0028
1
2.0116
1
2.0116
1
1.9832
1
  2.0135
1
2.0168
1
1.9860
1
  2.0244
1
    1.9760
1
1.9758
1
MP3         2.0310
13
  2.0365
14
        2.0550
4
2.0583
4
2.0322
4
        2.0230
4
2.0228
4
MP3=FULL         2.0354
14
  2.0382
14
        2.0642
3
2.0674
3
2.0380
3
        2.0278
3
2.0248
3
MP4   2.2790
11
    2.0596
15
    2.0309
2
2.0428
9
    2.0645
4
2.0670
4
2.0376
10
  2.0740
4
2.0388
4
  2.0293
4
2.0292
4
MP4=FULL   2.3036
4
    2.0474
4
      2.0621
4
      2.0662
4
2.0330
4
  2.0734
4
2.0296
4
  2.0215
4
2.0188
4
B2PLYP 2.2946
1
2.3616
1
2.0644
1
2.3096
1
2.0677
14
2.0807
1
2.0848
1
2.0961
1
2.0961
1
2.0801
1
  2.0977
1
2.0909
1
2.0466
11
  2.0927
1
2.0782
1
  2.0711
1
2.0699
1
B2PLYP=FULL 2.2945
1
2.3617
1
2.0645
1
2.3098
1
2.0804
1
2.0804
1
2.0845
1
2.0956
1
2.0956
1
2.0783
1
  2.0971
1
2.0907
1
2.0776
1
  2.0924
1
2.0745
1
  2.0681
1
2.0655
1
B2PLYP=FULLultrafine         2.0928
9
                             
Configuration interaction CID 2.2543
2
2.2660
11
2.0189
11
2.2300
11
2.0261
17
    2.0308
12
                    2.0086
4
2.0075
4
CISD 2.2474
2
2.2827
11
2.0214
11
2.2447
11
2.0295
17
    2.0345
11
                    2.0092
4
2.0081
4
Quadratic configuration interaction QCISD   2.3267
13
2.0463
13
2.2816
10
2.0430
17
2.0476
13
2.0519
15
2.0626
15
2.0613
17
2.0255
11
  2.0584
4
2.0660
13
2.0324
12
  2.0671
4
2.0325
4
  2.0241
4
2.0234
4
QCISD(T)         2.0605
15
    2.0803
4
      2.0667
4
2.0727
9
2.0374
9
  2.0548
7
2.0170
7
  2.0306
4
2.0309
4
Coupled Cluster CCD 2.2814
2
2.2921
13
2.0375
13
2.2598
13
2.0401
17
2.0398
13
2.0419
13
2.0497
14
2.0455
11
2.0200
11
  2.0549
4
2.0578
13
2.0210
9
  2.0368
7
2.0019
7
  2.0214
4
2.0208
4
CCSD         2.0371
15
    2.0264
2
      2.0572
4
2.0605
4
2.0325
4
2.0079
3
2.0659
4
2.0226
3
2.0077
3
2.0232
4
2.0225
4
CCSD=FULL         2.0397
4
            2.0560
4
2.0596
4
2.0266
4
2.0045
3
2.0653
4
2.0226
4
2.0037
3
2.0158
4
2.0124
4
CCSD(T)         2.0705
14
2.0545
3
  2.0907
4
    1.9917
2
2.0658
4
2.0677
10
2.0408
12
1.9830
4
2.0520
8
2.0143
8
2.0141
3
2.0300
4
2.0302
4
CCSD(T)=FULL         2.0456
6
            2.0649
4
2.0608
3
2.0339
4
1.9797
4
2.0741
4
2.0219
3
2.0100
3
2.0225
4
2.0196
4

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 2.1860
16
2.0286
17
2.1892
16
2.0289
17
2.3297
15
2.2908
15
density functional B1B95 2.2465
13
2.0869
10
       
B3LYP 2.2522
17
2.0868
17
2.2520
17
2.0856
17
2.2742
16
2.2794
17
Moller Plesset perturbation MP2 2.2702
17
2.0546
17
2.2692
17
2.0551
17
2.2845
17
2.2894
17
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.