National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
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VCost comparisons
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XOlder CCCBDB versions
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XIII Vibrations
XIVReaction data
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XIXIndex of properties
XXH-bond dimers
XXIOddities

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III.G.1.a.

Comparison of levels of theory for C-P


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 1.5859
10
PM3 1.6745
10
PM6 1.7127
13
composite G2 1.7174
12
G3 1.7096
13
G3B3 1.7212
13
G4 1.7257
12
CBS-Q 1.7104
13

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 1.7419
11
1.7559
13
1.7101
12
1.7569
13
1.7096
13
1.7091
13
1.7017
11
1.7060
13
1.7143
12
1.7041
13
1.6672
3
1.7137
13
1.7153
13
1.7063
13
1.6421
7
1.7177
13
1.7150
12
1.6423
7
1.5765
2
1.6446
1
ROHF   1.5661
1
1.5249
1
  1.5522
2
1.5241
1
1.5252
1
1.5216
1
        1.5330
1
1.5221
1
           
density functional LSDA 1.7357
13
1.7138
13
1.7047
13
1.7521
13
1.7105
13
1.7101
13
1.7104
13
1.7042
13
1.7045
13
1.7023
13
  1.7816
7
1.7161
13
1.7020
13
1.5961
1
1.7160
13
1.7182
10
1.5944
1
1.6561
1
1.6562
1
SVWN   1.7508
13
    1.7234
12
1.7798
7
1.7103
13
1.7747
7
1.7751
7
1.7719
7
  1.6315
7
1.7855
7
1.7723
7
  1.7857
7
1.7724
7
  1.6561
1
1.6562
1
BLYP 1.7917
11
1.7842
13
1.7336
13
1.7862
13
1.7378
13
1.7401
13
1.7410
13
1.7354
13
1.7489
12
1.7452
12
  1.8210
7
1.7456
13
1.7330
13
  1.7742
5
1.7884
3
  1.6777
1
1.6779
1
B1B95 1.7168
13
1.7174
13
1.7053
13
1.7536
13
1.7105
13
1.7111
13
1.7110
13
1.7067
13
1.7068
13
1.7047
13
  1.7883
7
1.7160
13
1.7050
13
1.5679
2
1.7163
13
1.7171
12
1.5675
2
1.6544
1
1.6547
1
B3LYP 1.7438
12
1.7647
13
1.7154
13
1.7665
13
1.7220
13
1.7216
13
1.7224
13
1.7172
13
1.7356
10
1.7145
13
1.8625
1
1.7228
13
1.7271
13
1.7154
13
1.6811
5
1.7280
13
1.7286
12
1.6811
5
1.5978
2
1.6629
1
B3LYPultrafine   1.8654
6
    1.7351
12
1.8205
6
1.8299
7
1.8165
6
      1.8246
6
1.8046
7
1.8034
8
  1.8058
7
1.7146
13
  1.6626
1
1.6629
1
B3PW91 1.7472
10
1.7724
12
1.7112
13
1.7734
12
1.7169
13
1.7165
13
1.7168
13
1.7119
13
1.7299
10
1.7101
13
  1.7964
7
1.7218
13
1.7106
13
  1.7205
6
1.7260
6
  1.6596
1
1.6598
1
mPW1PW91 1.7335
11
1.7552
13
1.7240
10
1.7692
12
1.7131
13
1.7127
13
1.7130
13
1.7083
13
1.7214
12
1.7192
12
  1.7927
7
1.7178
13
1.7072
13
  1.7753
9
1.7844
7
  1.6567
1
1.6570
1
M06-2X 1.7996
7
1.8260
7
1.7048
13
1.8269
7
1.7105
13
1.7890
7
1.7903
7
1.7860
7
1.7861
7
1.7614
9
  1.7917
7
1.7931
7
1.7633
9
  1.7944
7
1.7633
9
  1.6543
1
1.6546
1
PBEPBE 1.7630
10
1.7866
12
1.7415
10
1.7936
10
1.7432
12
1.7428
12
1.7431
12
1.7382
12
1.7385
12
1.7360
12
1.6950
3
1.8079
7
1.7479
12
1.7366
12
1.5856
2
1.7814
8
1.7581
10
1.5849
2
1.6732
1
1.6733
1
PBEPBEultrafine   1.8704
6
    1.7861
9
1.8251
6
1.8261
6
1.8208
6
      1.8284
6
1.8098
7
1.7993
7
  1.8108
7
1.7994
7
  1.6732
1
1.6733
1
PBE1PBE 1.8047
7
1.7793
7
1.7793
7
1.8309
7
1.7130
13
1.7894
7
1.7898
7
1.7848
7
1.7850
7
1.7826
7
  1.7922
7
1.7931
7
1.7839
7
  1.7945
7
1.7841
7
  1.6576
1
1.6579
1
HSEh1PBE 1.8060
7
1.7616
12
1.7795
7
1.8318
7
1.7273
12
1.7894
7
1.7211
12
1.7854
7
1.7856
7
1.7831
7
  1.7929
7
1.7939
7
1.7152
12
  1.7952
7
1.7847
7
  1.6580
1
1.6582
1
TPSSh 1.8503
1
1.8661
6
1.8086
6
1.8656
6
1.7210
13
1.8189
6
1.7210
13
1.8148
6
1.8058
1
1.6519
8
  1.8230
6
1.8239
6
1.7150
13
1.7967
1
1.8252
6
1.8137
6
1.7966
1
1.6641
1
1.6645
1
wB97X-D 1.8418
1
1.8579
1
1.6458
8
1.8594
1
1.6484
8
1.8041
1
1.6480
8
1.7983
1
1.6440
8
1.7943
1
  1.6473
8
1.6481
8
1.6421
8
1.7893
1
1.8076
1
1.6422
8
1.7891
1
   
B97D3   1.6799
7
    1.6622
7
      1.6586
7
              1.6380
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 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
Moller Plesset perturbation MP2 1.7801
10
1.7791
13
1.7178
13
1.7827
13
1.7317
13
1.7159
13
1.7164
13
1.7284
13
1.7120
13
1.7200
13
  1.7206
13
1.7285
13
1.7111
13
1.6397
4
1.7319
13
1.7113
13
1.6534
3
1.5785
3
1.6695
1
MP2=FULL 1.7795
10
1.7791
13
1.7354
10
1.8016
10
1.7134
13
1.7134
13
1.7141
13
1.7104
13
1.7302
10
1.7185
12
  1.7940
7
1.7266
13
1.7208
12
1.6284
5
1.7348
10
1.7440
10
1.6809
3
1.5724
3
1.6629
1
MP3         1.7251
12
  1.7213
13
        1.8176
6
1.8218
6
1.8072
6
        1.6640
1
1.6650
1
MP3=FULL   1.7607
2
1.7036
2
1.7715
2
1.6794
10
1.7056
2
1.7215
13
1.7020
2
1.7027
2
1.6960
2
  1.8168
6
1.8193
6
1.8004
6
  1.7236
2
1.6992
2
  1.6584
1
1.6590
1
MP4 1.6790
1
1.8090
10
    1.7379
12
    1.6609
4
1.7413
10
    1.8044
7
1.8081
7
1.7170
11
  1.8134
7
1.7938
7
  1.6778
1
1.6786
1
MP4=FULL   1.8554
7
    1.7937
7
      1.7911
7
      1.8055
7
1.7860
7
  1.8099
7
1.7408
4
  1.6718
1
1.6722
1
B2PLYP 1.8218
7
1.8416
7
1.7853
7
1.8446
7
1.7182
13
1.7936
7
1.7952
7
1.7900
7
1.7903
7
1.7680
9
  1.7989
7
1.8007
7
1.7118
13
  1.8034
7
1.7702
9
  1.6657
1
1.6661
1
B2PLYP=FULL 1.8216
7
1.8416
7
1.7851
7
1.8444
7
1.7935
7
1.7927
7
1.7944
7
1.7895
7
1.7898
7
1.7851
7
  1.7986
7
1.8000
7
1.7876
7
  1.8023
7
1.7878
7
  1.6639
1
1.6644
1
B2PLYP=FULLultrafine 1.7798
2
1.7565
2
1.7025
2
1.7666
2
1.7417
4
1.7109
2
1.7136
2
1.7061
2
1.7065
2
1.7015
2
  1.7150
2
1.7181
2
1.7045
2
  1.7224
2
1.7052
2
     
Configuration interaction CID   1.7849
10
1.7253
10
1.7886
10
1.7082
13
    1.7039
13
                    1.6540
1
1.6547
1
CISD   1.7669
11
1.7267
10
1.7986
9
1.7102
13
1.5379
1
  1.7234
10
                    1.6560
1
1.6566
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(T+d)Z aug-cc-pV(T+d)Z
Quadratic configuration interaction QCISD 1.6831
1
1.7810
13
1.7370
10
1.7982
10
1.7197
13
1.7369
10
1.7203
13
1.7165
13
1.7166
13
1.7257
12
  1.8009
7
1.7326
13
1.7145
13
  1.8091
7
1.7696
9
  1.6141
2
1.6687
1
QCISD(T)         1.7468
11
    1.7118
7
      1.8054
7
1.7558
10
1.7388
10
  1.7711
9
1.7507
9
  1.6770
1
1.6777
1
QCISD(T)=FULL         1.8128
6
  1.8136
6
          1.8251
6
1.8047
6
1.7888
1
1.8293
6
1.8428
5
     
QCISD(TQ)         1.8606
3
                             
Coupled Cluster CCD 1.6827
1
1.7959
10
1.7335
10
1.8005
10
1.7143
13
1.7331
10
1.7338
10
1.7105
13
1.7298
10
1.7276
10
  1.7984
7
1.7414
12
1.7289
10
  1.7499
10
1.7293
10
  1.6632
1
1.6639
1
CCSD         1.7403
11
    1.6624
4
  1.7254
6
  1.8003
7
1.8044
7
1.7687
9
1.7283
2
1.8086
7
1.7691
9
1.7284
2
1.6669
1
1.6675
1
CCSD=FULL         1.7711
9
        1.7041
5
  1.7993
7
1.8018
7
1.7623
9
1.7231
2
1.8053
7
1.7618
9
1.7841
1
1.6608
1
1.6611
1
CCSD(T)         1.7583
10
1.7138
7
  1.7112
7
      1.8051
7
1.7554
10
1.7384
10
1.6792
3
1.7596
10
1.7389
10
1.7346
2
1.6766
1
1.6773
1
CCSD(T)=FULL         1.7727
8
            1.8339
6
1.8064
7
1.7862
7
1.7293
2
1.8106
7
1.7827
3
1.6694
1
1.6706
1
1.6709
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(T+d)Z aug-cc-pV(T+d)Z

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 1.7669
13
1.7306
13
1.7652
13
1.7254
13
1.7776
11
1.7486
13
density functional B1B95 1.7128
4
1.7140
3
       
B3LYP 1.7826
13
1.7435
13
1.7803
13
1.7401
13
1.7968
11
1.7585
13
wB97X-D 1.8798
1
1.8239
1
1.8735
1
1.8205
1
1.8582
1
1.8481
1
Moller Plesset perturbation MP2 1.8018
13
1.7446
13
1.7947
13
1.7354
13
1.8333
11
1.7776
13
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.