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III.G.1.a.

Comparison of levels of theory for Na-Be


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 3.3937
1
composite G2 2.9620
1
G3 2.9620
1
G3B3 2.8738
1
G4 3.1187
1
CBS-Q 2.9621
1

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 2.4105
1
3.3915
1
3.3521
1
3.3158
1
3.2349
1
3.2349
1
3.2386
1
3.2543
1
3.2543
1
3.2121
1
3.2680
1
3.2841
1
3.2547
1
3.2499
1
3.2782
1
3.2530
1
3.2489
1
ROHF   3.3915
1
3.3521
1
3.3158
1
3.2349
1
3.2349
1
3.2386
1
3.2543
1
3.2543
1
  3.2680
1
3.2841
1
3.2547
1
3.2499
1
3.2782
1
3.2530
1
3.2489
1
density functional LSDA 2.3930
1
2.8717
1
2.8717
1
2.8225
1
2.8146
1
2.8146
1
2.8194
1
2.8139
1
2.8139
1
2.7869
1
2.7593
1
2.8237
1
2.8157
1
  2.7808
1
2.8136
1
 
SVWN   2.8874
1
    2.8146
1
2.8146
1
2.8194
1
2.8139
1
2.8139
1
2.7869
1
  2.8237
1
2.8157
1
  2.7808
1
2.8136
1
 
BLYP 2.4290
1
2.9276
1
2.9166
1
2.9037
1
2.8928
1
2.8928
1
2.9012
1
2.8962
1
2.8962
1
2.8695
1
2.8455
1
2.8969
1
2.8917
1
       
B1B95 2.4102
1
2.9982
1
2.9982
1
2.9663
1
2.9549
1
2.9549
1
2.9586
1
    2.9255
1
2.8944
1
2.9660
1
2.9579
1
       
B3LYP 2.4137
1
2.9387
1
2.9251
1
2.9089
1
2.8953
1
2.8953
1
2.9004
1
2.8965
1
2.8965
1
2.8727
1
2.8383
1
2.8990
1
2.8940
1
2.8849
1
2.8867
1
2.8925
1
2.8841
1
B3LYPultrafine         2.8955
1
                    3.1245
1
 
B3PW91 2.4160
1
2.9923
1
2.9808
1
2.9317
1
2.9182
1
2.9182
1
2.9206
1
2.9213
1
2.9213
1
2.8965
1
2.8600
1
2.9277
1
2.9185
1
       
mPW1PW91 2.4115
1
2.9750
1
2.9628
1
2.9211
1
2.9073
1
2.9073
1
2.9091
1
2.9108
1
2.9108
1
2.8866
1
2.8533
1
2.9169
1
2.9079
1
  2.9105
1
2.9072
1
 
M06-2X 2.3943
1
2.8964
1
2.8788
1
2.8990
1
2.8838
1
2.8838
1
2.8813
1
2.8714
1
2.8714
1
2.8600
1
2.8279
1
2.8833
1
2.8773
1
  2.8755
1
2.8769
1
 
PBEPBE 2.4217
1
2.9391
1
2.9289
1
2.8871
1
2.8783
1
2.8783
1
2.8838
1
2.8830
1
2.8830
1
2.8572
1
2.8335
1
2.8874
1
2.8805
1
  2.8729
1
2.8793
1
 
PBE1PBE 2.4086
1
2.9540
1
2.9540
1
2.9095
1
2.8972
1
2.8972
1
2.8995
1
2.8997
1
2.8997
1
2.8766
1
2.8428
1
2.9062
1
2.8984
1
  2.8993
1
2.8973
1
 
HSEh1PBE 2.4087
1
2.9654
1
2.9535
1
2.9101
1
2.8977
1
2.8977
1
2.9007
1
2.9012
1
2.9012
1
2.8781
1
2.8432
1
2.9073
1
2.8998
1
  2.9004
1
2.8987
1
 
TPSSh         2.8730
1
  2.8740
1
          2.8729
1
       
Moller Plesset perturbation MP2 2.4076
1
3.3945
1
3.2379
1
3.2815
1
3.0517
1
3.0517
1
3.0403
1
3.0265
1
3.0265
1
2.9899
1
3.1925
1
3.0749
1
3.0023
1
2.9858
1
3.0673
1
2.9983
1
2.9845
1
MP2=FULL 2.3975
1
3.3948
1
3.2276
1
3.2783
1
3.0297
1
3.0297
1
3.0156
1
2.9865
1
2.9865
1
2.9206
1
3.1745
1
3.0657
1
2.8517
1
2.9391
1
3.0149
1
2.9534
1
2.9161
1
ROMP2 2.4075
1
3.6769
1
3.6769
1
4.0056
1
3.3729
1
3.3729
1
3.3250
1
3.3002
1
3.3002
1
3.2188
1
4.6396
1
3.3960
1
3.2164
1
  3.3664
1
   
MP3         3.0195
1
  2.9076
1
                   
MP3=FULL         2.9023
1
  2.8984
1
                   
MP4   5.9019
1
    3.0154
1
      2.9747
1
      2.9600
1
       
Configuration interaction CID   4.2184
1
3.5254
1
4.1520
1
3.0862
1
    3.0267
1
                 
CISD   3.9381
1
3.6913
1
4.4563
1
3.2650
1
    3.1520
1
                 
Quadratic configuration interaction QCISD   3.9170
1
3.6706
1
4.3949
1
3.2473
1
3.2473
1
3.2125
1
3.1415
1
3.1415
1
3.0943
1
4.6947
1
3.1929
1
3.1008
1
  3.1901
1
3.0981
1
 
QCISD(T)         3.1949
1
          4.6094
1
3.1570
1
3.0658
1
  3.1526
1
3.0629
1
 
Coupled Cluster CCD   4.2184
1
3.5257
1
4.1520
1
3.0862
1
3.0862
1
3.0707
1
3.0267
1
3.0267
1
2.9979
1
5.1504
1
3.0834
1
3.0108
1
  3.0808
1
3.0075
1
 
CCSD         3.2623
1
            3.2034
1
3.1067
1
       
CCSD(T)         3.2031
1
          4.6097
1
3.1628
1
3.0688
1
3.0570
1
3.1571
1
3.0651
1
3.0548
1
CCSD(T)=FULL         3.1658
1
          4.5488
1
3.1489
1
2.8902
1
2.9844
1
3.1202
1
2.9015
1
2.9618
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 3.4527
1
3.3178
1
3.3251
1
3.2554
1
3.4877
1
3.3395
1
density functional B3LYP 2.9881
1
2.9710
1
2.9759
1
2.9620
1
3.0176
1
2.9124
1
Moller Plesset perturbation MP2 4.0139
1
3.0872
1
3.3044
1
3.0367
1
4.0070
1
3.2992
1
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.