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III.G.1.a.

Comparison of levels of theory for Cl-Li


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 2.4666
2
PM3 2.0369
3
PM6 2.5301
3
composite G2 2.2576
3
G3 2.2576
3
G3B3 2.2303
3
G4 2.2319
3
CBS-Q 2.2576
3

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 cc-pV(T+d)Z
hartree fock HF 2.0921
3
2.3052
3
2.2826
3
2.3392
3
2.2576
6
2.2576
3
2.2394
3
2.2033
3
2.2034
3
2.2258
3
2.0348
1
2.2577
3
2.2677
3
2.2045
3
2.1987
3
2.2390
3
2.1980
3
2.1957
3
2.2037
3
density functional LSDA 2.0640
3
2.2355
3
2.2294
3
2.2697
3
2.2060
3
2.2060
3
2.1947
3
2.1557
3
2.1557
3
2.1725
3
    2.2162
3
2.1536
3
2.2178
2
2.1842
3
2.2190
2
2.2146
2
 
SVWN   2.2438
3
    2.0917
2
  2.1948
3
                       
BLYP 2.0905
3
2.2668
3
2.2527
3
2.3004
3
2.2383
3
2.2383
3
2.2316
3
2.1998
3
2.1999
3
2.2115
3
    2.3324
2
2.2808
2
  2.0644
1
     
B1B95 2.1666
2
2.1907
1
2.1907
1
2.1591
2
2.1172
2
2.1172
2
2.0543
1
2.1926
3
2.1926
3
2.0958
2
    2.2506
3
2.0831
2
2.2651
2
2.1635
1
  2.1192
1
 
B3LYP 2.0824
3
2.2637
3
2.2475
3
2.2957
3
2.2301
3
2.2301
3
2.2203
3
2.1862
3
2.2672
2
2.2018
3
2.0216
1
2.2330
3
2.2374
3
2.2664
2
2.1773
3
2.2990
2
2.1789
3
2.1748
3
2.1846
3
B3LYPultrafine         2.2303
3
                      2.2221
3
   
B3PW91 2.1675
2
2.2856
3
2.2687
3
2.3166
3
2.2438
3
2.2438
3
2.2305
3
2.1922
3
2.2750
2
2.2137
3
    2.3469
2
2.2757
2
  2.0589
1
     
mPW1PW91 2.1621
2
2.2777
3
2.3526
2
2.3087
3
2.2369
3
2.2371
3
2.2240
3
2.1847
3
2.1849
3
2.2066
3
    2.3383
2
2.2667
2
  2.0557
1
     
M06-2X         2.2251
3
                           
PBEPBE 2.1617
2
2.2714
3
2.3458
2
2.4026
2
2.2368
3
2.2368
3
2.2277
3
2.1912
3
2.1912
3
2.2075
3
2.0254
1
  2.2450
3
2.1895
3
2.2584
2
    2.2548
2
 
PBEPBEultrafine         2.0609
1
                           
PBE1PBE         2.2319
3
                           
HSEh1PBE         2.2324
3
                           
TPSSh         2.1336
3
  2.1270
3
            2.1116
3
         
Moller Plesset perturbation MP2 2.1603
2
2.3073
3
2.2737
3
2.3459
3
2.1934
4
2.2347
3
2.2186
3
2.1749
3
2.1750
3
2.3065
2
  2.2468
3
2.2621
3
2.2866
2
2.2006
3
2.2552
3
2.2066
3
2.0443
1
2.2050
3
MP2=FULL 2.1602
2
2.3063
3
2.3642
2
2.4519
2
2.1893
4
2.2303
3
2.2134
3
2.1672
3
2.2425
2
2.2758
2
    2.3483
2
2.1905
3
2.1769
3
2.0505
1
    2.1849
3
MP3         2.2316
3
  2.1382
3
                       
MP3=FULL         2.1355
3
  2.1252
3
                       
MP4   2.4010
2
    2.2332
3
    2.0222
1
2.2462
2
        2.0419
1
         
B2PLYP         2.2269
3
                2.1121
3
         
Configuration interaction CID   2.4015
2
2.3659
2
2.4551
2
2.2337
3
    2.1726
3
                     
CISD   2.4016
2
2.3664
2
2.4556
2
2.2342
3
    2.2492
2
                     
Quadratic configuration interaction QCISD   2.3091
3
2.3661
2
2.4566
2
2.2335
3
2.3162
2
2.2177
3
2.1721
3
2.1722
3
2.3041
2
    2.2613
3
2.2026
3
         
QCISD(T)         2.2337
3
    2.0227
1
        2.3497
2
2.2835
2
  2.3411
2
2.2842
2
   
Coupled Cluster CCD   2.4018
2
2.3654
2
2.4558
2
2.2327
3
2.3157
2
2.2948
2
2.1712
3
2.2467
2
2.3039
2
    2.2604
3
2.2835
2
  2.3384
2
2.2819
2
   
CCSD         2.2336
3
    2.0216
1
                     
CCSD(T)         2.0697
1
2.0697
1
  2.0225
1
    2.0414
1
  2.2610
3
2.2028
3
2.2780
2
2.2564
3
2.2055
3
   
CCSD(T)=FULL         2.3114
2
                  2.2501
2
       

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 2.4022
3
2.2940
3
2.2915
3
2.2112
3
2.3126
3
2.3112
3
density functional B1B95 2.1585
1
2.1049
1
       
B3LYP 2.3890
3
2.2960
3
2.2942
3
2.2227
3
2.2813
3
2.2804
3
Moller Plesset perturbation MP2 2.4035
3
2.2820
3
2.3014
3
2.1954
3
2.3053
3
2.3130
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.