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Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
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III.G.1.a.

Comparison of levels of theory for S-S


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 1.9072
11
PM3 1.8743
9
PM6 1.9767
27
composite G2 1.9560
28
G3 1.9560
28
G3B3 2.0223
28
G3MP2 1.8788
2
G4 2.0062
27
CBS-Q 1.9559
18

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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ
hartree fock HF 2.0306
25
2.1918
27
1.9841
28
2.1516
28
1.9934
28
1.9934
28
2.0044
21
2.0004
28
2.0101
25
1.9911
26
1.9926
16
2.0054
28
2.0078
28
1.9877
28
1.8968
10
2.0070
28
1.9894
27
1.9167
8
1.9560
9
1.9795
20
1.9268
9
1.9431
4
1.9312
5
1.8992
1
ROHF   2.1712
5
1.9521
5
2.1666
3
1.9636
5
1.9637
5
1.9648
5
1.9705
5
2.0054
3
    2.0089
3
1.9755
5
1.9544
5
1.9815
1
2.0076
3
1.9861
3
1.9812
1
1.9481
3
1.9759
2
    1.9791
1
 
density functional LSDA 2.0477
28
2.1132
28
1.9917
28
2.1553
28
2.0064
28
2.0065
28
2.0056
28
2.0081
28
2.0084
28
1.9861
28
  2.0382
5
2.0145
28
1.9902
28
  2.0124
28
1.9773
8
2.0007
1
1.9670
6
1.9530
4
1.9520
4
  1.9524
1
 
SVWN   2.1786
28
    2.0157
25
2.0331
5
2.0053
28
2.0372
5
2.0380
5
2.0106
5
  2.0039
23
2.0401
5
2.0159
5
  2.0387
5
2.0148
5
  1.9649
4
1.9264
5
1.9520
4
  1.9524
1
 
BLYP 2.0952
25
2.2409
28
2.0419
28
2.2113
28
1.9884
32
2.0571
27
2.0576
28
2.0643
28
2.0753
25
2.0196
16
  2.0967
5
2.0651
28
2.0410
28
  2.0980
13
    1.9907
7
1.9706
5
1.9691
5
  1.9995
1
 
B1B95 2.0490
26
2.1120
28
1.9883
28
2.1524
28
1.9994
28
2.0010
28
2.0005
28
2.0048
28
2.0109
26
1.9904
26
  2.0329
5
2.0097
28
1.9871
28
1.8988
4
2.0068
28
1.9616
14
1.8976
4
1.9452
7
1.9301
9
1.9296
9
1.9627
4
1.9396
5
 
B3LYP 2.0714
25
2.2095
28
2.0133
28
2.1797
28
2.0280
28
2.0281
28
2.0276
28
2.0327
28
2.0081
13
2.0074
27
2.0425
12
2.0334
28
2.0944
28
2.0136
28
1.9372
10
2.0344
28
1.9831
27
1.9387
8
1.9808
9
2.0030
22
1.9506
9
1.9867
4
1.9616
5
1.9415
1
B3LYPultrafine         2.0315
27
  1.9894
7
          2.0137
1
2.0312
16
  2.0144
1
2.0072
28
          1.9797
1
 
B3PW91 2.0614
21
2.1966
27
1.9982
28
2.1614
26
2.0111
28
2.0113
28
2.0107
28
2.0146
28
1.9905
13
1.9736
17
  2.0455
5
2.0200
28
1.9978
28
  2.0430
14
1.8871
1
  1.9541
7
1.9356
5
1.9350
5
  1.9641
1
 
mPW1PW91 2.0551
21
2.1854
28
1.9972
25
2.1585
27
2.0066
28
2.0048
28
2.0043
28
2.0082
28
2.0183
25
1.9706
17
  2.0386
5
2.0135
28
1.9921
28
  2.0147
10
2.0178
5
  1.9493
7
1.9309
5
1.9304
5
  1.9597
1
 
M06-2X 2.0511
5
2.2075
5
1.9665
32
2.1789
5
2.0034
28
2.0306
5
2.0307
5
2.0362
5
2.0368
5
1.9910
6
  2.0507
3
2.0383
5
1.9941
6
  2.0369
5
1.9932
6
  1.8606
3
1.9326
5
1.9321
5
  1.9604
1
 
PBEPBE 2.0771
21
2.1921
19
1.9922
14
2.1594
14
2.0067
18
2.0069
18
2.0062
18
2.0107
18
2.0448
25
2.0192
25
2.0353
13
2.0641
5
2.0120
19
1.9919
18
1.9303
3
2.0246
8
2.0287
12
1.9283
3
1.9673
7
1.9542
9
1.9590
8
2.0088
3
1.9785
4
1.9220
1
PBEPBEultrafine         2.0458
19
              2.0079
1
1.9884
1
  2.0097
1
1.9885
1
          1.9767
1
 
PBE1PBE 2.0233
1
1.9692
1
1.9692
1
2.1440
1
1.9965
24
1.9837
1
1.9857
1
1.9890
1
1.9900
1
1.9650
1
  1.9906
1
1.9913
1
1.9697
1
  1.9918
1
1.9696
1
    2.0460
2
2.0462
2
  1.9585
1
 
HSEh1PBE 2.0594
5
2.1881
27
2.0188
5
2.1862
5
2.0114
26
2.0315
5
2.0107
26
2.0381
5
2.0391
5
2.0138
5
  2.0387
5
2.0401
5
1.9987
26
  2.0388
5
2.0177
5
  1.9089
4
1.9309
5
1.9304
5
  1.9596
1
 
TPSSh         1.9678
28
  1.9676
28
    1.9604
28
      1.9616
28
                   
wB97X-D     1.9614
32
  1.9677
32
      1.9680
32
        1.9614
32
    1.9611
32
             
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ
Moller Plesset perturbation MP2 2.0685
21
2.2489
26
1.9928
28
2.2119
28
1.9641
28
2.0066
28
2.0061
28
1.9637
28
2.0149
26
1.9687
16
  2.0158
28
2.0250
28
1.9928
26
1.9247
6
2.0281
28
1.9733
17
1.9253
4
1.9712
9
1.9833
23
1.9489
7
1.9843
4
1.9513
5
1.9278
1
MP2=FULL 2.0733
20
2.2479
27
2.0006
24
2.2211
24
2.0051
28
2.0050
28
2.0048
28
1.9837
20
1.9876
13
1.9645
13
  2.0379
5
2.0212
27
1.9940
26
1.9230
4
1.9921
13
1.9985
11
1.8952
2
1.9689
9
1.9765
23
1.9395
7
1.9825
4
1.9471
5
1.9282
1
ROMP2 2.0446
3
1.9839
3
1.9839
3
2.1730
3
1.9990
3
1.9993
3
1.9994
3
2.0051
3
2.0054
3
1.9829
3
  2.0099
3
2.0147
3
1.9869
3
  2.0178
3
            1.9511
1
 
MP3         2.0133
27
  1.9646
28
                      1.9585
3
1.8871
2
1.8851
2
  1.9695
1
 
MP3=FULL         1.9641
28
  1.9638
28
                                 
MP4 2.1214
8
2.2665
24
    2.0200
28
    2.0140
2
1.9936
10
    2.0099
1
2.0145
1
1.9853
13
  2.0196
1
1.9841
1
  1.9772
7
1.8762
3
1.8735
3
  1.9726
1
 
MP4=FULL   2.2169
1
    1.9963
1
      2.0042
1
      2.0129
1
1.9794
1
  2.0186
1
1.9763
1
          1.9690
1
 
B2PLYP         2.0116
23
  1.9031
2
  1.9007
2
1.8931
1
      1.9528
23
    1.8940
1
  1.8722
1
1.8671
1
1.8654
1
     
B2PLYP=FULL   1.9884
2
    1.9001
2
  1.8999
2
                                 
B2PLYP=FULLultrafine         2.0383
15
                                     
Configuration interaction CID 2.1038
8
2.2254
23
1.9686
15
2.1653
15
1.9988
28
2.0535
1
  1.9844
17
        2.0749
1
          1.8197
1
1.8054
1
1.8055
1
  1.9668
1
 
CISD 2.1039
8
2.2300
23
1.9648
14
2.1654
14
2.0550
28
2.0538
1
  1.9796
14
        2.0753
1
          1.8218
1
1.8075
1
1.8075
1
  1.9682
1
 
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ
Quadratic configuration interaction QCISD 2.1214
10
2.2773
27
2.0107
24
2.2345
24
2.0704
28
2.0236
24
2.0126
27
2.0208
28
2.0104
16
1.9930
11
  2.0546
5
2.0073
19
1.9858
16
  2.0651
5
2.0062
6
  1.9802
9
1.9564
11
1.9460
5
  1.9799
1
 
QCISD(T)         2.0202
27
1.9591
2
1.9593
2
1.9882
4
2.0909
2
    2.0621
5
2.0189
10
1.9900
10
  2.0235
10
2.0005
8
  2.0090
3
1.9928
3
1.9930
3
  1.9824
1
 
Coupled Cluster CCD 2.1198
10
2.2532
24
2.0060
24
2.2183
24
2.0103
28
2.0193
24
2.0193
24
2.0223
26
2.0163
10
1.9991
10
  2.0473
5
2.0092
17
1.9878
12
  2.0167
8
1.9845
8
  1.9758
9
1.9404
10
1.9273
8
1.9425
2
1.9286
3
 
CCSD   2.1739
2
    1.9830
19
1.9386
2
1.9384
2
1.9713
4
2.0831
2
1.8854
1
  2.0147
1
2.0120
8
1.9734
9
1.9730
1
2.0239
1
1.9372
2
1.9729
1
1.9995
3
1.9974
3
1.9532
4
  1.9776
1
 
CCSD=FULL         1.9236
3
        1.8814
1
  2.0142
1
1.9548
2
1.9146
3
1.9692
1
1.9600
2
1.9112
3
1.9686
1
  1.8623
1
1.8587
1
  1.9731
1
 
CCSD(T)   2.2196
2
    2.0249
25
1.9647
6
1.9571
2
1.9865
4
2.0905
2
  1.9040
1
2.0606
5
2.0060
14
1.9748
16
1.9467
2
2.0101
14
1.9721
7
1.9765
1
2.0064
5
1.9734
7
1.9850
6
1.9945
4
1.9639
5
 
CCSD(T)=FULL         2.0083
10
            2.0600
5
2.0532
7
2.0207
7
1.9434
2
2.0602
7
2.0176
7
1.9725
1
1.9865
7
1.9491
9
1.9736
7
1.9921
4
1.9602
5
 
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ

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 2.1483
28
2.0075
28
2.1493
28
2.0061
28
2.1777
27
2.1796
27
density functional B1B95 2.1924
18
2.0465
18
2.2355
2
2.0865
2
2.2615
2
2.2448
2
B3LYP 2.1912
28
2.0441
28
2.1889
28
2.0412
28
2.2198
27
2.2055
28
Moller Plesset perturbation MP2 2.2122
28
2.0255
28
2.2112
28
2.0217
28
2.2375
27
2.2351
27
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.