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III.G.1.a.

Comparison of levels of theory for As-C


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 PM6 2.0024
3
composite G2 1.9562
3
G3 1.9562
3
G3B3 1.9937
3
G4 1.9832
3

average calculated bond lengths (Å)
Methods with standard basis sets
3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF 1.9837
3
1.9760
3
1.9728
3
1.9562
6
1.9553
3
1.9565
3
1.9673
3
1.9754
3
1.9689
3
1.9656
3
1.9638
3
1.9695
3
1.9654
3
density functional BLYP 2.0126
3
2.0174
3
2.0214
3
2.0025
3
2.0007
3
2.0045
3
2.0153
3
  2.0176
3
2.0122
3
     
B1B95 1.9766
3
1.9729
3
1.9721
3
1.9518
3
1.9509
3
1.9530
3
1.9664
3
  1.9672
3
1.9633
3
  1.9677
3
 
B3LYP 1.9939
3
1.9940
3
1.9953
3
1.9763
3
1.9749
3
1.9777
3
1.9888
3
1.9918
3
1.9912
3
1.9858
3
1.9833
3
1.9917
3
1.9854
3
B3LYPultrafine       1.9764
3
                1.9859
3
B3PW91 1.9854
3
1.9832
3
1.9825
3
1.9628
3
1.9617
3
1.9639
3
1.9759
3
  1.9779
3
1.9729
3
     
mPW1PW91 1.9811
3
1.9779
3
1.9767
3
1.9571
3
1.9560
3
1.9579
3
1.9703
3
  1.9719
3
1.9673
3
     
PBEPBE 1.9971
3
1.9977
3
1.9981
3
1.9773
3
1.9759
3
1.9787
3
1.9912
3
  1.9927
3
1.9881
3
  1.9931
3
 
PBEPBEultrafine       1.9774
3
                 
PBE1PBE       1.9553
3
                 
TPSSh       1.9666
3
  1.9696
3
      1.9786
3
     
Moller Plesset perturbation MP2 1.9972
3
1.9872
3
1.9938
3
1.9600
3
1.9585
3
1.9603
3
1.9702
3
1.9641
3
1.9697
3
1.9502
6
  1.9729
3
1.9520
3
MP2=FULL 1.9962
3
1.9861
3
1.9914
3
1.9528
3
1.9512
3
1.9528
3
1.9638
3
  1.9664
3
1.9394
6
     
MP3       1.9638
3
  1.9602
3
             
MP3=FULL       1.9550
3
  1.9567
3
             
MP4 2.0056
3
    1.9697
3
                 
B2PLYP                   1.9724
3
     
Configuration interaction CID 1.9923
3
1.9827
3
1.9868
3
1.9551
3
    1.9643
3
           
CISD 1.9932
3
1.9834
3
1.9877
3
1.9557
3
    1.9650
3
           
Quadratic configuration interaction QCISD 2.0056
3
1.9961
3
2.0034
3
1.9675
3
1.9664
3
1.9684
3
1.9772
3
  1.9777
3
1.9587
3
     
QCISD(T) 2.0081
3
    1.9714
3
1.9701
3
1.9722
3
1.9815
3
  1.9817
3
    1.9855
3
 
Coupled Cluster CCD 2.0031
3
1.9936
3
2.0006
3
1.9652
3
1.9640
3
1.9659
3
1.9748
3
  1.9757
3
1.9573
3
     
CCSD 2.0051
3
    1.9670
3
1.9659
3
1.9679
3
1.9766
3
  1.9775
3
1.9585
3
     
CCSD(T) 2.0079
3
    1.9712
3
1.9698
3
1.9720
3
1.9813
3
  1.9816
3
    1.9854
3
 
CCSD(T)=FULL       1.9642
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 1.9867
3
  1.9884
3
  1.9831
3
1.9833
3
density functional B3LYP 2.0121
3
  2.0135
3
  2.0042
3
2.0036
3
Moller Plesset perturbation MP2 2.0197
3
  2.0191
3
  2.0113
3
2.0132
3
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.