National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
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III.G.1.a.

Comparison of levels of theory for C-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 1.6325
44
PM3 1.6692
41
PM6 1.7213
148
composite G2 1.7746
119
G3 1.7719
138
G3B3 1.7832
148
G3MP2 1.7492
8
G4 1.7753
147
CBS-Q 1.7593
83

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 Def2TZVPP 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 1.7560
138
1.8345
148
1.7629
140
1.8264
139
1.7651
151
1.7632
138
1.7209
58
1.7644
140
1.7641
139
1.7597
140
1.7727
117
1.7359
149
1.7511
152
1.7696
140
1.7600
139
1.6577
28
1.7710
140
1.7605
139
1.6379
19
1.7439
3
1.7039
24
1.7413
3
1.6662
5
1.6731
7
1.8117
2
ROHF 1.6293
4
1.7226
10
1.6688
11
1.7210
10
1.6442
12
1.6747
11
1.6734
11
1.6734
11
1.6595
10
1.6020
4
1.7215
2
1.6974
6
1.7221
2
1.6791
11
1.6693
11
1.6491
9
1.6535
10
1.6293
10
1.6192
9
  1.5895
1
    1.8030
1
 
density functional LSDA 1.7839
104
1.8358
99
1.7660
103
1.8268
105
1.7628
118
1.7646
117
1.7641
117
1.7625
116
1.7650
115
1.7547
117
1.6908
2
1.6861
10
1.6936
2
1.7676
116
1.7552
117
1.5937
4
1.7669
115
1.6932
28
1.5874
4
1.7317
3
1.6756
5
1.7903
2
1.8054
2
1.7309
4
 
BLYP 1.8229
138
1.8755
140
1.7846
88
1.8727
140
1.7876
154
1.8049
140
1.8042
138
1.7831
87
1.8042
139
1.7952
139
1.7013
5
1.7542
25
1.7015
5
1.8074
137
1.7946
138
  1.8242
120
1.7634
21
  1.7765
3
1.7120
5
1.8491
2
1.8627
2
1.7820
4
 
B1B95 1.7813
136
1.7390
7
1.7653
136
1.8249
137
1.7612
137
1.7639
136
1.7642
138
1.7625
136
1.7628
136
1.7559
134
1.6764
5
1.7195
25
1.6771
5
1.7671
136
1.7545
137
1.5808
6
1.7739
129
1.7254
58
1.5932
4
1.7382
3
1.6435
7
1.7370
3
1.6666
5
1.6681
7
 
B3LYP 1.7963
139
1.8536
148
1.7825
140
1.8461
141
1.7847
148
1.7827
140
1.7839
145
1.7813
140
1.7258
45
1.7769
148
1.7866
107
1.7456
149
1.7612
152
1.7863
140
1.7746
137
1.6417
19
1.7522
67
1.7740
147
1.6395
19
1.7571
3
1.7147
24
1.7536
3
1.6805
5
1.6814
7
1.8234
2
B3LYPultrafine   1.8157
21
    1.7805
138
1.7537
21
1.7906
48
1.7516
21
  1.6961
5
1.6887
5
1.7549
21
1.6890
5
1.7384
25
1.7783
73
  1.7386
25
1.7727
150
  1.8292
2
1.6951
5
1.8272
2
1.8403
2
1.7636
4
 
B3PW91 1.7379
45
1.8398
139
1.7711
141
1.8332
141
1.7881
140
1.7886
140
1.7522
87
1.7696
139
1.7166
45
1.7633
139
1.6817
5
1.7272
25
1.6825
5
1.7754
139
1.7623
138
  1.7899
120
1.7495
33
  1.7456
3
1.6873
5
1.8131
2
1.8253
2
1.7523
4
 
mPW1PW91 1.7280
46
1.8322
139
1.7231
52
1.8273
140
1.7658
141
1.7664
139
1.7663
140
1.7654
140
1.7656
139
1.7593
139
1.6795
5
1.7237
25
1.6802
5
1.7691
137
1.7244
67
  1.7818
126
1.7227
26
  1.7413
3
1.6842
5
1.8091
2
1.8201
2
1.7491
4
 
M06-2X 1.7244
25
1.7770
25
1.7694
150
1.7743
25
1.7290
139
1.7230
25
1.7222
25
1.7212
25
1.7214
25
1.7351
38
1.6842
5
1.7238
25
1.6840
5
1.7255
25
1.7316
39
  1.7260
25
1.7350
38
  1.7445
3
1.6846
5
1.8143
2
1.8241
2
1.7528
4
 
PBEPBE 1.7497
46
1.8529
140
1.7177
40
1.7792
40
1.7827
139
1.7845
139
1.7841
139
1.7831
139
1.7836
139
1.7763
137
1.7881
107
1.7383
25
1.7629
152
1.7861
133
1.7758
140
1.5967
6
1.7552
28
1.7625
55
1.5922
6
1.7565
3
1.6371
9
1.8243
2
1.7000
4
1.6959
6
1.8215
2
PBEPBEultrafine   1.8087
22
    1.7929
131
1.7549
21
1.7542
21
1.7528
21
  1.6973
5
1.6893
5
1.7559
21
1.6900
5
1.7402
25
1.7244
26
  1.7402
25
1.7288
25
  1.8247
2
1.6988
5
1.8243
2
1.8350
2
1.7622
4
 
PBE1PBE 1.7297
25
1.6923
5
1.7209
25
1.7707
26
1.7661
142
1.7219
25
1.7205
25
1.7193
25
1.7196
25
1.7144
25
1.6791
5
1.7229
25
1.6798
5
1.7243
25
1.7095
26
  1.7247
25
1.7140
25
  1.8079
2
1.7059
4
1.8073
2
1.8181
2
1.7477
4
 
HSEh1PBE 1.7307
25
1.7706
138
1.7212
25
1.7717
26
1.7267
138
1.7224
25
1.7230
136
1.7200
24
1.7204
25
1.7151
25
1.6738
4
1.7237
25
1.6801
5
1.7252
25
1.7179
137
  1.7256
25
1.7147
25
  1.7411
3
1.6844
5
1.8084
2
1.8195
2
1.7485
4
 
TPSSh 1.7619
20
1.8077
22
1.7445
22
1.8031
22
1.7685
151
1.7510
21
1.7691
150
1.7491
21
1.7449
20
1.7680
150
1.6869
5
1.7527
21
1.6874
5
1.7546
20
1.7623
151
1.7020
8
1.7544
21
1.7432
21
1.7011
8
1.8252
2
1.7183
4
1.8241
2
1.8359
2
1.7621
4
 
wB97X-D 1.7500
20
1.7950
20
1.7620
153
1.7919
20
1.7615
153
1.7379
20
1.7621
152
1.7362
20
1.7609
152
1.7309
20
1.6838
5
1.7635
152
1.6841
5
1.7625
152
1.7554
153
1.6937
8
1.7416
20
1.7563
152
1.6931
8
1.8136
2
1.7085
4
1.8126
2
1.8244
2
1.7512
4
 
B97D3 1.7987
15
1.8179
151
1.7638
16
1.8275
16
1.7747
151
1.7759
15
1.7756
150
1.7737
15
1.7739
150
1.7678
15
1.7634
152
1.7771
15
1.6905
5
1.7780
15
1.7681
151
1.7258
5
1.7790
15
1.7800
150
1.7246
5
1.8312
2
1.8296
2
1.8299
2
1.8427
2
1.8309
2
 
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 Def2TZVPP 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 1.7414
45
1.8568
149
1.7753
141
1.8505
140
1.7624
155
1.7628
140
1.7655
148
1.7604
150
1.7608
139
1.7552
93
1.6794
5
1.7359
149
1.7498
152
1.7745
140
1.7446
108
1.6606
13
1.7478
68
1.7150
61
1.6593
13
1.7508
3
1.7073
24
1.7450
3
1.6797
5
1.6764
7
1.8198
2
MP2=FULL 1.7416
45
1.8200
70
1.7231
47
1.7960
47
1.7572
140
1.7435
88
1.7433
88
1.7600
139
1.7095
45
1.7120
52
1.6752
5
1.7235
25
1.6767
5
1.7435
69
1.7117
67
1.6570
13
1.7089
30
1.7046
46
1.6654
12
1.7484
3
1.6976
26
1.7373
3
1.6775
5
1.6725
7
1.8186
2
ROMP2 1.7018
6
1.6449
2
1.6652
6
1.7454
6
1.6597
6
1.6594
6
1.6571
6
1.6555
6
1.6554
6
1.6522
6
  1.6693
4
  1.6719
6
1.6542
6
1.6361
1
1.6728
6
1.6336
3
1.6361
1
  1.6095
1
    1.7741
1
 
MP3         1.7649
140
  1.7587
151
      1.6859
5
1.7460
21
1.6859
5
1.7509
21
1.7306
22
        1.7534
3
1.7129
4
1.8188
2
1.8322
2
1.7581
4
 
MP3=FULL   1.8172
20
1.7452
20
1.8071
21
1.7580
151
1.7337
20
1.7580
149
1.7334
20
1.7328
20
1.7264
20
1.6823
5
1.7452
21
1.6834
5
1.7490
21
1.7254
22
  1.7492
20
1.7003
12
  1.8208
2
1.7068
4
1.8104
2
1.8302
2
1.7537
4
 
MP4   1.7907
35
1.5812
1
1.6758
1
1.7131
49
1.5723
1
1.5692
1
1.6728
3
1.6969
31
  1.6392
2
1.7327
21
1.6389
2
1.7313
22
1.6436
25
  1.7426
21
1.6814
11
  1.7612
3
1.7004
5
1.8232
2
1.8376
2
1.7640
4
 
MP4=FULL   1.7599
16
    1.7192
22
      1.7235
21
  1.6350
2
  1.6359
2
1.7364
21
1.7199
17
  1.7402
21
1.6747
11
  1.8250
2
1.7158
4
1.8148
2
1.8353
2
1.7595
4
 
B2PLYP 1.7523
23
1.8018
24
1.7350
24
1.7994
24
1.7357
137
1.7392
23
1.7473
29
1.7374
23
1.7431
28
1.7505
36
1.6868
5
1.7422
23
1.6872
5
1.7450
23
1.7643
150
  1.7468
23
1.7505
36
  1.8237
2
1.7173
4
1.8215
2
1.8335
2
1.7603
4
 
B2PLYP=FULL 1.7522
23
1.8108
31
1.7349
24
1.7993
24
1.7468
31
1.7384
23
1.7517
30
1.7370
23
1.7370
23
1.7307
23
1.6855
5
1.7419
23
1.6862
5
1.7443
23
1.7256
24
  1.7460
23
1.7307
23
  1.8228
2
1.7153
4
1.8191
2
1.8328
2
1.7590
4
 
B2PLYP=FULLultrafine 1.7578
20
1.8050
21
1.7379
21
1.8022
21
1.7950
112
1.7423
20
1.7418
20
1.7411
20
1.7410
20
1.7347
20
1.6855
5
1.7460
20
1.6863
5
1.7478
20
1.7285
21
  1.7502
20
1.7352
20
  1.8228
2
1.7153
4
1.8191
2
1.8328
2
1.7590
4
 
Configuration interaction CID   1.7899
46
1.7202
46
1.7870
47
1.7416
89
1.7597
5
1.5277
1
1.7049
43
    1.6826
5
  1.6828
5
1.7121
8
1.6508
7
        1.8182
2
1.6820
5
1.8105
2
1.8269
2
1.7524
4
 
CISD   1.8001
49
1.7169
44
1.7905
44
1.7429
89
1.7651
6
1.5331
1
1.6992
40
    1.6838
5
  1.6840
5
1.7140
8
1.6523
7
        1.8195
2
1.6836
5
1.8113
2
1.8283
2
1.7537
4
 
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 Def2TZVPP 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 1.8861
4
1.8447
100
1.7304
47
1.8035
45
1.7399
70
1.7284
48
1.7238
56
1.7408
69
1.7384
67
1.7278
51
1.6922
5
1.7346
25
1.6926
5
1.7331
53
1.7138
50
  1.7432
25
1.7479
36
  1.7578
3
1.6325
9
1.8196
2
1.8352
2
1.7614
4
 
QCISD(T)   1.6206
1
1.5647
1
1.6250
1
1.7031
44
1.5564
1
1.5531
1
1.7339
18
1.8177
2
  1.6390
2
1.7375
22
1.6388
2
1.7021
31
1.6785
31
  1.7096
30
1.6426
19
  1.8301
2
1.6998
5
1.8238
2
1.8397
2
1.7357
5
 
QCISD(T)=FULL         1.7408
19
  1.7484
18
      1.6348
2
  1.6358
2
1.7598
18
1.6788
11
1.6851
5
1.7296
12
1.6943
8
1.6743
3
1.8269
2
1.7164
4
1.8155
2
1.8373
2
1.7316
5
 
QCISD(TQ)         1.7128
4
  1.7521
3
            1.7621
3
1.7094
4
  1.7692
3
1.6225
1
             
QCISD(TQ)=FULL         1.7107
4
  1.7499
3
            1.7600
3
1.6177
1
  1.7667
3
1.6174
1
             
Coupled Cluster CCD 1.8544
4
1.7951
44
1.7233
44
1.7924
45
1.7736
93
1.7142
44
1.7102
45
1.7150
45
1.7069
38
1.7044
38
1.6872
5
1.7280
25
1.6873
5
1.7253
52
1.6842
37
  1.7019
33
1.6546
25
  1.7535
3
1.6492
7
1.7468
3
1.6783
5
1.6764
7
 
CCSD   1.6020
1
1.5506
1
1.6072
1
1.7238
52
1.6765
6
1.6741
6
1.6863
8
1.7337
7
1.7553
34
1.6908
5
1.7326
25
1.6913
5
1.7308
26
1.7380
39
1.6784
11
1.7414
25
1.7356
28
1.6485
6
1.8258
2
1.6927
5
1.8192
2
1.8348
2
1.7301
5
 
CCSD=FULL         1.7404
39
        1.7484
34
1.6866
5
1.7317
25
1.6882
5
1.7342
24
1.7319
38
1.6714
10
1.7391
25
1.7287
28
1.6461
6
1.8228
2
1.7094
4
1.8105
2
1.8323
2
1.7254
5
 
CCSD(T)   1.6223
4
1.5620
1
1.6212
1
1.7224
37
1.7283
25
1.7206
16
1.7164
20
1.7303
18
1.7684
12
1.6069
3
1.7367
22
1.6382
2
1.6961
33
1.6384
28
1.6748
7
1.7033
32
1.6378
21
1.6740
7
1.7624
3
1.6410
8
1.7554
3
1.6884
5
1.6855
7
 
CCSD(T)=FULL         1.7101
25
          1.6343
2
1.7357
22
1.6353
2
1.7262
24
1.6533
17
1.6626
8
1.6954
18
1.6576
13
1.6448
7
1.7597
3
1.6626
6
1.6711
5
1.6861
5
1.6817
7
 
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 Def2TZVPP 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)
daug-cc-pVDZ daug-cc-pVTZ daug-cc-pVQZ Sadlej_pVTZ CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF       1.8117
2
1.8324
140
1.7754
141
1.8308
139
1.7737
141
1.8240
137
1.8193
140
density functional B1B95         1.8633
115
1.8025
114
1.8837
4
1.8222
4
1.8761
4
1.8664
4
B3LYP       1.8234
2
1.8608
139
1.7968
140
1.8569
140
1.7936
132
1.8491
137
1.8378
137
PBEPBE       1.8215
2
           
wB97X-D         1.8103
20
1.7510
21
1.8061
20
1.7467
21
1.7847
21
1.7853
20
Moller Plesset perturbation MP2       1.8198
2
1.8645
140
1.7816
138
1.8610
140
1.7773
140
1.8529
140
1.8505
140
MP2=FULL       1.8186
2
           
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.