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III.G.1.a.

Comparison of levels of theory for C-B


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 1.3228
6
PM3 1.8411
4
PM6 1.3287
8
composite G2 1.4726
6
G3 1.4726
6
G3B3 1.4634
6
G4 1.4616
5
CBS-Q 1.4769
6

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 1.4504
6
1.4696
6
1.4696
6
1.4679
6
1.4872
8
1.4740
6
1.4755
6
1.4706
6
1.4706
6
1.4776
6
1.4682
6
1.4835
6
1.4700
6
1.4672
6
1.4847
6
1.4709
6
1.4679
6
ROHF 1.3318
1
1.4293
2
1.4293
2
1.4293
2
1.4128
2
1.4128
2
1.4160
2
1.4105
2
1.4105
2
1.3890
1
1.4280
1
1.4204
2
1.4111
2
1.4091
2
1.4214
2
1.4119
2
1.4103
2
density functional LSDA 1.4553
5
1.4800
5
1.4800
5
1.4814
5
1.4659
5
1.4659
5
1.4673
5
1.4586
5
1.4586
5
1.4649
5
1.4850
1
1.4726
5
1.4579
5
1.4535
2
1.4716
5
1.4584
5
1.4543
2
SVWN   1.4710
6
    1.4643
2
1.4950
1
1.4576
6
1.4870
1
1.4870
1
1.4939
1
  1.5002
1
1.4859
1
  1.4973
1
1.4852
1
 
BLYP 1.4619
6
1.4853
6
1.4853
6
1.4870
6
1.4845
6
1.4845
6
1.4858
6
1.4780
6
1.4780
6
1.4829
6
1.4988
1
1.4900
6
1.4760
6
       
B1B95 1.4458
6
1.4731
6
1.4731
6
1.4735
6
1.4566
6
1.4566
6
1.4534
5
1.4529
6
1.4529
6
1.4562
6
1.4821
1
1.4632
6
1.4519
6
1.4435
5
1.4629
6
1.4586
6
1.4519
5
B3LYP 1.4511
6
1.4802
6
1.4802
6
1.4815
6
1.4634
6
1.4634
6
1.4653
6
1.4586
6
1.4586
6
1.4625
6
1.4570
6
1.4700
6
1.4569
6
1.4551
6
1.4696
6
1.4575
6
1.4559
6
B3LYPultrafine         1.4634
6
            1.4971
1
1.4838
1
  1.4942
1
1.4718
5
 
B3PW91 1.4471
6
1.4807
6
1.4807
6
1.4730
6
1.4634
6
1.4634
6
1.4647
6
1.4588
6
1.4588
6
1.4628
6
1.4801
1
1.4696
6
1.4577
6
       
mPW1PW91 1.4434
6
1.4699
6
1.4699
6
1.4704
6
1.4611
6
1.4611
6
1.4623
6
1.4568
6
1.4568
6
1.4606
6
1.4757
1
1.4674
6
1.4489
6
  1.4875
1
1.4767
1
 
M06-2X 1.4797
1
1.5080
1
1.5080
1
1.5052
1
1.4611
6
1.4827
1
1.4803
1
1.4769
1
1.4769
1
1.4812
1
1.4728
1
1.4876
1
1.4759
1
  1.4853
1
1.4746
1
 
PBEPBE 1.4585
6
1.4846
6
1.4846
6
1.4852
6
1.4833
6
1.4833
6
1.4842
6
1.4813
6
1.4813
6
1.4860
6
1.4972
1
1.4878
6
1.4801
6
1.4750
5
1.4850
3
1.4742
3
1.4761
5
PBEPBEultrafine         1.5066
1
            1.5103
1
1.4980
1
  1.5079
1
1.4973
1
 
PBE1PBE 1.4838
1
1.5130
1
1.5130
1
1.5107
1
1.4619
6
1.4872
1
1.4849
1
1.4810
1
1.4810
1
1.4867
1
1.4778
1
1.4915
1
1.4798
1
  1.4893
1
1.4790
1
 
HSEh1PBE 1.4845
1
1.5131
1
1.5131
1
1.5108
1
1.4617
6
1.4871
1
1.4848
1
1.4809
1
1.4809
1
1.4867
1
1.4777
1
1.4916
1
1.4795
1
  1.4893
1
1.4787
1
 
TPSSh         1.4349
6
  1.4352
6
          1.4295
6
       
Moller Plesset perturbation MP2 1.4362
5
1.4779
5
1.4779
5
1.4693
5
1.4511
5
1.4511
5
1.4544
5
1.4561
5
1.4561
5
1.4512
5
1.4401
6
1.4668
5
1.4530
5
1.4489
5
1.4678
5
1.4535
5
1.4823
1
MP2=FULL 1.4361
5
1.4778
5
1.4778
5
1.4752
5
1.4493
5
1.4493
5
1.4525
5
1.4550
5
1.4550
5
1.4472
5
1.4809
1
1.4659
5
1.4470
5
1.4448
5
1.4834
3
1.4608
4
1.4745
1
ROMP2 1.4494
2
1.5103
2
1.5103
2
1.5065
2
1.4674
2
1.4674
2
1.4666
2
1.4707
2
1.4707
2
1.4698
2
1.4771
1
1.4884
2
1.4650
2
1.4407
1
1.4875
2
1.4490
1
1.4429
1
MP3         1.4549
5
  1.4298
6
                   
MP3=FULL         1.4286
6
  1.4306
6
                   
MP4   1.4864
3
    1.4579
6
      1.4507
5
  1.5149
1
  1.4728
3
    1.5181
1
 
MP4=FULL         1.5157
1
              1.5005
1
    1.4922
1
 
B2PLYP         1.4585
5
              1.4242
4
       
Configuration interaction CID   1.4827
4
1.4827
4
1.4694
4
1.4442
4
    1.4503
4
                 
CISD   1.4776
4
1.4776
4
1.4820
4
1.4566
5
    1.4616
5
                 
Quadratic configuration interaction QCISD   1.5007
6
1.5007
6
1.5017
6
1.4618
5
1.4682
6
1.4708
6
1.4789
6
1.4789
6
1.4692
6
1.4906
1
1.4874
6
1.4586
5
  1.5142
1
1.4900
1
 
QCISD(T)         1.4707
4
          1.5055
1
1.5002
5
1.4469
3
  1.4925
4
1.4695
4
 
Coupled Cluster CCD   1.4639
5
1.4639
5
1.4715
6
1.4496
6
1.4496
6
1.4534
6
1.4475
6
1.4475
6
1.4415
5
1.4794
1
1.4685
6
1.4498
6
  1.4698
6
1.4383
5
 
CCSD         1.4678
5
          1.4900
1
1.5164
1
1.4900
1
1.4822
1
1.5142
1
1.4892
1
1.4822
1
CCSD=FULL         1.4912
1
          1.4877
1
1.5149
1
1.4799
1
1.4752
1
1.5123
1
1.4743
1
1.4750
1
CCSD(T)         1.4883
4
          1.5066
1
1.4890
5
1.4789
4
1.4590
5
1.4898
5
1.4655
5
1.4683
3
CCSD(T)=FULL         1.4704
4
          1.5046
1
1.5317
1
1.4971
1
1.4607
3
1.5291
1
1.4912
1
1.4617
3

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 1.5029
6
1.4638
6
1.5747
6
1.4508
6
1.4889
6
1.4899
6
density functional B3LYP 1.5184
6
1.4937
6
1.5108
6
1.4813
6
1.5000
6
1.5011
6
Moller Plesset perturbation MP2 1.5073
5
1.4749
5
1.4880
5
1.4588
5
1.4903
5
1.4898
5
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.