return to home page

III.G.1.a.

Comparison of levels of theory for B-N


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 1.2717
13
PM3 1.2083
2
PM6 1.3391
14
composite G2 1.3653
14
G3 1.3653
14
G3B3 1.3778
14
G4 1.3885
12
CBS-Q 1.3653
14

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
hartree fock HF 1.3635
14
1.3863
14
1.3863
14
1.3795
14
1.3749
22
1.3649
14
1.3659
14
1.3611
14
1.3613
14
1.3612
14
1.2879
2
1.3626
14
1.3654
14
1.3612
14
1.3591
14
1.3659
14
1.3614
14
1.3593
14
ROHF 1.2637
3
1.2875
3
1.2765
2
1.2715
2
1.2629
4
1.2680
3
1.2691
3
1.2543
2
1.2642
3
1.2651
3
  1.2889
1
1.2695
3
1.2650
3
1.2875
1
1.2594
2
1.2549
2
1.2877
1
density functional LSDA 1.3879
12
1.3992
12
1.3992
12
1.3921
12
1.3830
12
1.3825
12
1.3838
12
1.3778
12
1.3781
12
1.3786
12
  1.2947
2
1.3830
12
1.3775
12
  1.3826
12
1.2841
3
 
SVWN   1.3899
14
    1.3729
14
1.3014
2
1.3737
14
1.2937
2
1.2937
2
1.2989
2
    1.3035
2
1.2940
2
  1.3013
2
1.2938
2
 
BLYP 1.3981
14
1.4084
14
1.4084
14
1.4020
14
1.3915
14
1.3911
14
1.3927
14
1.3866
14
1.3870
14
1.3873
14
  1.3070
2
1.3910
14
1.3863
14
       
B1B95 1.3784
14
1.4036
13
1.4036
13
1.3858
14
1.3853
13
1.3853
13
1.3863
13
1.3705
14
1.3708
14
1.3820
13
  1.2895
2
1.3750
14
1.3701
14
1.2794
4
1.3747
14
1.3745
13
1.2799
4
B3LYP 1.3840
14
1.3964
14
1.3964
14
1.3906
14
1.3790
14
1.3786
14
1.3800
14
1.3742
14
1.3746
14
1.3750
14
  1.3760
14
1.3794
14
1.3741
14
1.3720
14
1.3788
14
1.3744
14
1.3307
8
B3LYPultrafine   1.3198
2
    1.3831
13
1.2980
2
1.2984
2
1.2913
2
      1.2922
2
1.2996
2
1.2916
2
  1.2979
2
1.3886
12
 
B3PW91 1.3806
14
1.3949
14
1.3949
14
1.3878
14
1.3770
14
1.3767
14
1.3776
14
1.3725
14
1.3728
14
1.3733
14
  1.2917
2
1.3770
14
1.3723
14
       
mPW1PW91 1.3773
14
1.3924
14
1.3924
14
1.3853
14
1.3745
14
1.3741
14
1.3751
14
1.3701
14
1.3703
14
1.3708
14
  1.2888
2
1.3744
14
1.3699
14
  1.2946
2
1.2886
2
 
M06-2X 1.2946
2
1.3088
2
1.3088
2
1.3024
2
1.3734
14
1.2883
2
1.2887
2
1.2821
2
1.2821
2
1.2858
2
  1.2830
2
1.2889
2
1.2837
2
  1.2881
2
1.2834
2
 
PBEPBE 1.3916
14
1.4052
14
1.4052
14
1.3982
14
1.3872
14
1.3868
14
1.3880
14
1.3826
14
1.3829
14
1.3834
14
  1.3060
2
1.3871
14
1.3824
14
1.2933
4
1.3018
3
1.3052
4
1.2939
4
PBEPBEultrafine   1.3333
2
    1.3209
3
1.3115
2
1.3116
2
1.3051
2
      1.3060
2
1.3132
2
1.3052
2
  1.3115
2
1.3052
2
 
PBE1PBE 1.3029
2
1.3178
2
1.3178
2
1.3113
2
1.3749
14
1.2953
2
1.2954
2
1.2893
2
1.2893
2
1.2932
2
  1.2901
2
1.2970
2
1.2899
2
  1.2957
2
1.2899
2
 
HSEh1PBE 1.3034
2
1.3175
2
1.3175
2
1.3113
2
1.3751
14
1.2952
2
1.2953
2
1.2891
2
1.2891
2
1.2930
2
  1.2899
2
1.2970
2
1.2897
2
  1.2956
2
1.2896
2
 
TPSSh   1.3274
2
1.3274
2
1.3204
2
1.3771
12
1.3043
2
1.3776
12
1.2981
2
      1.2988
2
1.3060
2
1.3744
12
  1.3046
2
1.2982
2
 
Moller Plesset perturbation MP2 1.3720
14
1.4029
14
1.4029
14
1.3984
14
1.3817
14
1.3811
14
1.3839
14
1.3800
14
1.3803
14
1.3766
14
  1.3808
14
1.3857
14
1.3790
14
1.3513
7
1.3895
14
1.3624
6
1.2987
5
MP2=FULL 1.3719
14
1.4025
14
1.4025
14
1.3981
14
1.3800
14
1.3794
14
1.3821
14
1.3787
14
1.3789
14
1.3710
14
  1.3213
2
1.3847
14
1.3737
14
1.3478
7
1.4049
12
1.3994
4
1.2926
4
ROMP2 1.2912
2
1.3158
2
1.3158
2
1.3114
2
1.2910
2
1.2912
2
1.2928
2
1.2876
2
1.2876
2
1.2863
2
  1.3292
1
1.2965
2
1.2874
2
  1.2985
2
   
MP3         1.3734
14
  1.3709
12
        1.2895
2
1.2998
2
1.2886
2
       
MP3=FULL         1.3693
12
  1.3711
12
        1.2880
2
1.2991
2
1.2832
2
       
MP4 1.3130
2
1.3734
8
    1.3876
14
      1.3508
8
1.3220
2
  1.3327
2
1.3379
2
1.3158
6
  1.3406
2
1.3306
2
 
MP4=FULL   1.3521
2
    1.3293
2
      1.3314
2
      1.3372
2
1.3252
2
  1.3395
2
1.3240
2
 
B2PLYP 1.3191
2
1.3373
2
1.3373
2
1.3315
2
1.3846
14
1.3110
2
1.3119
2
1.3065
2
1.3065
2
1.3079
2
  1.3071
2
1.3149
2
1.3765
12
  1.3141
2
1.3066
2
 
B2PLYP=FULL 1.3191
2
1.3373
2
1.3373
2
1.3314
2
1.3105
2
1.3105
2
1.3114
2
1.3061
2
1.3061
2
1.3063
2
  1.3066
2
1.3146
2
1.3046
2
  1.3137
2
1.3043
2
 
Configuration interaction CID 1.3103
2
1.3972
14
1.3972
14
1.3923
14
1.3733
14
  1.3122
2
1.3700
14
1.3068
2
1.3061
2
    1.3153
2
1.3060
2
       
CISD 1.3418
2
1.4030
14
1.4030
14
1.3980
14
1.3764
14
  1.3181
2
1.3730
14
1.3144
2
1.3130
2
    1.3237
2
1.3124
2
       
Quadratic configuration interaction QCISD 1.3672
2
1.4125
14
1.4125
14
1.4066
14
1.3841
14
1.3836
14
1.3853
14
1.3805
13
1.2893
5
1.3021
6
  1.2914
2
1.3888
14
1.3018
6
  1.3021
2
1.2908
2
 
QCISD(T) 1.3651
2
      1.3134
7
      1.3410
2
1.3386
2
  1.3162
2
1.3395
6
1.3238
6
  1.3380
5
1.3217
5
 
QCISD(T)=FULL         1.3177
2
  1.3191
2
          1.3261
2
1.3061
2
1.3011
2
1.3260
2
1.3042
2
1.3016
2
QCISD(TQ)         1.3323
2
  1.3337
2
          1.3403
2
1.3250
2
1.3181
2
1.3415
2
1.3257
2
1.3185
2
QCISD(TQ)=FULL         1.3308
2
  1.3321
2
          1.3396
2
1.3190
2
1.3138
2
1.3402
2
1.3172
2
1.3255
1
Coupled Cluster CCD 1.3114
2
1.4031
14
1.4031
14
1.3986
14
1.3793
14
1.3788
14
1.3810
14
1.3767
14
1.2998
6
1.2968
6
  1.3082
2
1.3836
14
1.2969
6
  1.3072
5
1.2947
5
 
CCSD         1.3038
5
      1.3257
2
1.3243
2
  1.3041
2
1.3217
3
1.3089
3
1.2953
2
1.3150
2
1.3019
2
1.2958
2
CCSD=FULL         1.3065
2
            1.3024
2
1.3138
2
1.2954
2
1.2910
2
1.3133
2
1.2935
2
1.2913
2
CCSD(T) 1.3546
2
      1.3062
7
      1.3358
2
1.3341
2
1.3307
2
1.3053
2
1.3130
7
1.3012
7
1.3004
5
1.3085
6
1.2966
6
1.3089
4
CCSD(T)=FULL         1.3090
5
            1.3037
2
1.3087
3
1.2923
3
1.2963
5
1.3093
3
1.2912
3
1.3046
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 1.3982
13
1.3761
14
1.3872
14
1.3701
14
1.3883
14
1.3881
14
density functional B1B95 1.3590
2
1.3377
1
       
B3LYP 1.4040
14
1.3935
14
1.4001
14
1.3874
14
1.3972
14
1.3975
14
Moller Plesset perturbation MP2 1.4121
14
1.3924
14
1.4033
14
1.3858
14
1.4060
14
1.4054
14
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.