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III.G.1.a.

Comparison of levels of theory for Cl-F


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 1.6773
9
PM3 1.6744
15
PM6 1.6650
12
composite G2 1.7380
11
G3 1.7248
12
G3B3 1.7345
12
G4 1.6412
11
CBS-Q 1.7275
12

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(D+d)Z cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ
hartree fock HF 1.8502
17
1.8547
17
1.7268
12
1.8589
15
1.7299
23
1.7248
12
1.7361
12
1.7472
12
1.7472
12
1.7008
12
1.5940
5
1.7217
12
1.7258
12
1.7009
12
1.5786
7
1.7400
12
1.7109
12
1.5785
7
1.6171
1
1.6927
12
1.6468
4
1.5969
9
ROHF         1.5311
1
                                 
density functional LSDA 1.8563
11
1.7281
11
1.6741
11
1.8648
12
1.7112
12
1.7112
12
1.6793
11
1.6899
11
1.7360
12
1.6420
11
    1.6847
11
1.6554
11
  1.6887
11
1.5459
1
  1.6361
1
1.6198
1
   
SVWN   1.8395
12
    1.7243
11
  1.7236
12
                             
BLYP 1.9168
11
1.9147
17
1.7954
12
1.9948
4
1.7803
12
1.7803
12
1.7975
12
1.8389
7
1.8117
12
1.7580
12
    1.8022
12
1.7723
12
  1.7627
5
    1.6656
1
1.6503
1
   
B1B95 1.8489
11
1.7646
12
1.7198
12
1.8556
12
1.7094
12
1.7112
12
1.6686
11
1.7311
12
1.7311
12
1.6900
12
    1.7292
12
1.6415
11
1.5306
1
1.6756
11
1.7229
7
1.5311
1
1.6371
1
1.6182
1
   
B3LYP 1.8654
11
1.8480
12
1.7444
12
1.8774
12
1.7344
12
1.7344
12
1.7449
12
1.7571
12
1.7866
7
1.6594
11
1.6697
5
1.7538
12
1.7529
12
1.7218
12
1.6550
7
1.7543
11
1.7271
11
1.6552
7
1.6494
1
1.7098
12
1.7096
4
1.6708
9
B3LYPultrafine         1.7341
12
  1.7184
3
            1.6866
4
    1.7432
12
         
B3PW91 1.8553
6
1.8370
12
1.7323
12
1.8666
12
1.7218
12
1.7219
12
1.6801
11
1.7422
12
1.7718
7
1.7003
12
    1.7396
12
1.7071
12
  1.6995
5
    1.6423
1
1.6241
1
   
mPW1PW91 1.8439
6
1.8238
12
1.7499
7
1.8547
12
1.7122
12
1.7122
12
1.6704
11
1.7310
12
1.7311
12
1.6907
12
    1.7294
12
1.6456
11
  1.6898
5
    1.6383
1
1.6197
1
   
M06-2X         1.6939
12
                          1.6347
1
1.6171
1
   
PBEPBE 1.9011
6
1.8911
11
1.7962
7
1.9322
10
1.7543
12
1.7543
12
1.7181
11
1.7822
12
1.7823
12
1.7333
12
1.6906
5
  1.7756
12
1.6914
11
1.5636
1
  1.7030
4
1.5637
1
1.6548
1
1.6512
1
   
PBEPBEultrafine         1.7132
9
                                 
PBE1PBE         1.7100
12
                                 
HSEh1PBE         1.7127
12
                          1.6390
1
1.6204
1
   
TPSSh         1.6898
12
  1.6961
12
            1.6816
12
               
Moller Plesset perturbation MP2   1.8659
12
1.7379
12
1.8732
11
1.6747
16
1.6712
11
1.7164
18
1.6921
11
1.6921
11
1.6351
6
  1.7225
12
1.6951
11
1.6547
16
1.6296
1
1.7313
11
1.7393
3
1.6302
1
1.6815
1
1.6720
12
1.7027
4
1.6509
9
MP2=FULL 7.0778
5
1.8635
11
1.7656
7
1.8604
6
1.6722
16
1.6685
11
1.7174
12
1.6907
11
1.6789
6
1.6304
6
    1.6918
10
1.6496
11
1.6269
1
1.7101
9
      1.6693
12
1.7021
4
1.6497
9
MP3         1.6598
11
  1.6784
12
                        1.6208
1
   
MP3=FULL         1.6767
12
  1.6823
12
                             
MP4   2.0538
2
    1.7219
11
    1.6886
1
1.7648
7
        1.7236
6
        1.6815
1
1.6412
1
   
B2PLYP         1.7246
12
                1.6781
12
               
B2PLYP=FULLultrafine         1.6928
4
                                 
Configuration interaction CID   1.8529
7
1.7605
7
1.8483
7
1.6383
11
    1.6361
7
                      1.6117
1
   
CISD   1.8452
7
1.7523
7
1.7858
6
1.6397
11
    1.6349
6
                    1.6435
1
1.6133
1
   
Quadratic configuration interaction QCISD   1.9053
7
1.7737
7
2.0511
2
1.6692
10
1.6592
6
1.7352
8
1.7402
11
1.7628
7
1.5531
1
    1.7537
8
1.5900
2
        1.6521
1
1.6279
1
   
QCISD(T)         1.8241
3
    1.6891
1
        1.9169
2
1.8652
2
  1.8944
2
1.8589
2
  1.6836
1
1.6386
1
   
Coupled Cluster CCD   1.8886
7
1.7713
7
1.8844
7
1.6593
11
1.6496
6
1.7195
7
1.6636
7
1.5585
1
1.5306
1
    1.6699
7
1.5264
1
  1.8305
2
1.5294
1
  1.6489
1
1.6209
1
1.6932
4
1.6407
4
CCSD         1.6588
6
    1.6753
1
                    1.6515
1
1.6233
1
   
CCSD(T)   1.7868
1
    1.6892
5
1.6734
1
1.6785
1
1.6886
1
1.6886
1
  1.6422
1
  1.8433
3
1.7933
3
  1.8274
3
1.7899
3
  1.6834
1
1.6465
6
1.7159
4
1.6591
4
CCSD(T)=FULL         1.8227
3
              1.6944
1
1.6422
1
  1.6835
1
1.6422
1
  1.6824
1
1.6436
6
1.7147
4
1.6575
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 1.8936
10
1.7374
11
1.8904
10
1.7390
11
1.8611
10
1.8607
10
density functional B1B95 1.8453
5
1.6881
5
       
B3LYP 1.9122
11
1.7607
11
1.9083
11
1.7605
11
1.9146
11
1.9141
11
Moller Plesset perturbation MP2 1.8400
4
1.6985
7
1.9107
5
1.7057
10
1.8509
4
1.9254
5
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.