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III.G.1.a.

Comparison of levels of theory for Br-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 1.7801
4
PM3 1.8306
4
PM6 1.8994
4
composite G2 1.9000
4
G3 1.9137
4
G3B3 1.9192
4
G4 1.9055
1
CBS-Q 1.8956
4

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 1.8869
4
1.9462
4
1.8954
4
1.9149
4
1.9017
4
1.9017
4
1.8992
4
1.9112
4
1.9112
4
1.8903
4
1.9098
4
1.9112
4
1.9086
4
1.9026
1
1.9137
4
1.9086
4
1.9025
1
density functional LSDA 1.8725
4
1.8692
4
1.8692
4
1.8882
4
1.8803
4
1.8803
4
1.8778
4
1.8884
4
1.8884
4
1.8656
4
1.8845
4
1.8925
4
1.8825
4
  1.8905
4
1.8817
4
 
SVWN   1.9125
4
    1.8803
4
1.8803
4
1.8778
4
1.8884
4
1.8884
4
1.8656
4
  1.8925
4
1.8825
4
  1.8905
4
1.8817
4
 
BLYP 1.9048
4
1.9583
4
1.9074
4
1.9320
4
1.9209
4
1.9209
4
1.9176
4
1.9303
4
1.9303
4
1.9034
4
1.9262
4
1.9326
4
1.9237
4
       
B1B95 1.8811
4
1.8810
4
1.8810
4
1.8994
4
1.8886
4
1.8886
4
1.8862
4
1.8982
4
1.8982
4
1.8763
4
1.8954
4
1.8996
4
1.8940
4
  1.8995
4
1.8937
4
 
B3LYP 1.8926
4
1.9410
4
1.8934
4
1.9150
4
1.9045
4
1.9045
4
1.9017
4
1.9139
4
1.9139
4
1.8894
4
1.9102
4
1.9159
4
1.9082
4
1.9012
1
1.9150
4
1.9077
4
1.9007
1
B3LYPultrafine         1.9048
4
            1.9162
4
1.9085
4
  1.9153
4
1.9080
4
 
B3PW91 1.8871
4
1.9346
4
1.8878
4
1.9065
4
1.8963
4
1.8963
4
1.8937
4
1.9058
4
1.9058
4
1.8826
4
1.9029
4
1.9073
4
1.9009
4
       
mPW1PW91 1.8838
4
1.9310
4
1.8849
4
1.9029
4
1.8927
4
1.8927
4
1.8902
4
1.9023
4
1.9023
4
1.8796
4
1.8997
4
1.9036
4
1.8978
4
  1.9036
4
1.8974
4
 
M06-2X 1.8809
4
1.9351
4
1.8893
4
1.9043
4
1.8947
4
1.8947
4
1.8920
4
1.9036
4
1.9036
4
1.8829
4
1.9032
4
1.9049
4
1.9012
4
  1.9053
4
1.9008
4
 
PBEPBE 1.8924
4
1.9447
4
1.8961
4
1.9164
4
1.9057
4
1.9057
4
1.9026
4
1.9155
4
1.9155
4
1.8907
4
1.9124
4
1.9170
4
1.9100
4
  1.9161
4
1.9095
4
 
PBEPBEultrafine         1.9061
4
            1.9175
4
1.9105
4
  1.9165
4
1.9100
4
 
PBE1PBE 1.8819
4
1.8844
4
1.8844
4
1.9020
4
1.8917
4
1.8917
4
1.8892
4
1.9014
4
1.9014
4
1.8788
4
1.8988
4
1.9026
4
1.8970
4
  1.9026
4
1.8968
4
 
HSEh1PBE 1.8829
4
1.9321
4
1.8860
4
1.9040
4
1.8935
4
1.8935
4
1.8910
4
1.9033
4
1.9033
4
1.8803
4
1.9007
4
1.9046
4
1.8988
4
  1.9045
4
1.8985
4
 
TPSSh         1.8955
3
  1.8955
3
          1.9052
3
       
Moller Plesset perturbation MP2 1.8940
4
1.9509
4
1.8986
4
1.9226
4
1.8989
4
1.8989
4
1.8961
4
1.9010
4
1.9010
4
1.8791
4
1.8956
4
1.9060
4
1.8891
4
1.8777
1
1.9083
4
1.8876
4
1.8769
1
MP2=FULL 1.8939
4
1.9507
4
1.8973
4
1.9209
4
1.8939
4
1.8939
4
1.8912
4
1.8967
4
1.8967
4
1.8620
4
1.8951
4
1.9038
4
1.8791
4
1.8709
1
1.9060
4
1.8723
4
1.8695
1
MP3         1.9033
4
  1.9012
4
                   
MP3=FULL         1.8976
3
  1.8980
3
                   
MP4   1.9655
4
    1.9075
4
      1.9112
4
  1.9062
4
1.9163
4
1.9002
4
  1.9194
4
1.8966
1
 
MP4=FULL   1.9653
4
    1.9025
4
      1.9078
4
    1.9140
4
1.8899
4
  1.9171
4
1.8764
1
 
Configuration interaction CID   1.9530
4
1.8990
4
1.9248
4
1.8998
4
    1.9040
4
                 
CISD   1.9557
4
1.8996
4
1.9267
4
1.9006
4
    1.9048
4
                 
Quadratic configuration interaction QCISD   1.9632
4
1.9065
4
1.9333
4
1.9073
4
1.9073
4
1.9049
4
1.9106
4
1.9106
4
1.8880
4
1.9063
4
1.9154
4
1.8994
4
  1.9185
4
1.8976
4
 
QCISD(T)         1.9082
4
          1.9078
4
1.9169
4
1.9012
4
  1.9204
4
1.8997
4
 
Coupled Cluster CCD   1.9567
4
1.9041
4
1.9285
4
1.9044
4
1.9044
4
1.9020
4
1.9074
4
1.9074
4
1.8855
4
1.9031
4
1.9121
4
1.8968
4
  1.9152
4
1.8952
4
 
CCSD         1.9057
4
          1.9049
4
1.9136
4
1.8981
4
1.8925
1
1.9168
4
1.8964
4
1.8922
1
CCSD=FULL         1.9007
4
          1.9042
4
1.9114
4
1.8881
4
1.8851
1
1.9145
4
1.8761
1
1.8842
1
CCSD(T)         1.9072
4
          1.9069
4
1.9159
4
1.9003
4
1.8948
1
1.9192
4
1.8989
4
1.8941
1
CCSD(T)=FULL         1.9022
4
          1.9062
4
1.9136
4
1.8902
4
1.8875
1
1.9169
4
1.8785
1
1.8869
1

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 1.9570
4
  1.9561
4
  1.9641
4
1.9509
4
density functional B3LYP 1.9720
4
  1.9702
4
  1.9712
4
1.9598
4
Moller Plesset perturbation MP2 1.9777
4
  1.9722
4
  1.9753
4
1.9648
4
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.