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III.G.1.a.

Comparison of levels of theory for P-Cl


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 1.8169
3
PM3 2.0424
15
PM6 2.0135
15
composite G2 2.0599
12
G3 2.0474
15
G3B3 2.0816
15
G4 2.0600
15
CBS-Q 2.0342
10
molecular mechanics DREIDING 1.8770
5

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 2.1241
14
2.2269
15
2.0392
15
2.2042
15
2.0478
40
2.0475
15
2.0479
15
2.0529
15
2.0529
15
2.0411
15
2.0348
12
2.0601
15
2.0649
15
2.0446
15
2.0362
4
2.0660
15
2.0443
15
2.0339
4
2.0387
14
ROHF         2.1393
2
                           
density functional LSDA 2.1435
15
2.1801
15
2.0390
15
2.2031
15
2.0546
15
2.0546
15
2.0544
15
2.0577
15
2.0577
15
2.0351
15
    2.0653
15
2.0395
15
2.0235
2
2.0642
15
2.0179
3
2.0187
2
 
SVWN   2.2118
15
    2.0579
12
  2.0550
15
                       
BLYP 2.1972
14
2.2867
15
2.0971
15
2.2710
15
2.1129
15
2.1129
15
2.1136
15
2.1030
10
2.1211
15
2.0943
15
    2.1243
15
2.0998
15
  2.1280
12
     
B1B95 2.1459
15
2.1866
15
2.0414
15
2.2072
15
2.0513
15
2.0538
15
2.0634
14
2.0578
15
2.0578
15
2.0397
15
    2.0661
15
2.0409
15
2.0204
3
2.0632
15
2.0240
3
2.0171
3
 
B3LYP 2.1658
15
2.2529
15
2.0672
15
2.2369
15
2.0816
15
2.0817
15
2.0819
15
2.0874
15
2.0765
3
2.0664
15
2.0610
12
2.0896
15
2.0941
15
2.0706
15
2.0460
4
2.0885
7
2.0644
7
2.0431
4
2.0622
14
B3LYPultrafine         2.0816
15
                2.0767
11
    2.0625
15
   
B3PW91 2.1282
3
2.2347
15
2.0519
15
2.2183
15
2.0647
15
2.0648
15
2.0491
10
2.0684
15
2.0553
3
2.0498
15
    2.0767
15
2.0538
15
  2.0803
12
     
mPW1PW91 2.0873
4
2.2264
15
2.0394
3
2.2100
15
2.0576
15
2.0577
15
2.0575
15
2.0611
15
2.0612
15
2.0434
15
    2.0697
15
2.0427
7
  2.0734
12
     
M06-2X         2.0561
15
                           
PBEPBE 2.1397
3
2.2546
15
2.0606
3
2.2211
3
2.0841
15
2.0841
15
2.0843
15
2.0897
15
2.0896
15
2.0664
15
2.0623
12
  2.0920
12
2.0712
15
2.0563
2
2.0518
1
2.0645
5
2.0405
3
 
PBEPBEultrafine         2.0890
23
                           
PBE1PBE         2.0559
15
                           
HSEh1PBE         2.0607
14
                           
TPSSh         2.0433
15
  2.0429
15
            2.0359
15
         
Moller Plesset perturbation MP2 2.1259
3
2.2740
15
2.0383
15
2.2547
15
2.0380
18
2.0504
15
2.0504
15
2.0548
15
2.0548
15
2.0407
15
  2.0622
15
2.0716
15
2.0213
10
2.0275
3
2.0788
7
2.0309
4
2.0251
3
2.0372
14
MP2=FULL 2.1256
3
2.2677
7
2.0338
3
2.2406
3
2.0369
18
2.0346
10
2.0343
10
2.0539
15
2.0442
3
2.0220
3
    2.0684
7
1.9993
6
2.0237
3
2.0763
5
2.0010
1
2.0223
2
2.0165
9
MP3         2.0539
15
  2.0340
15
                       
MP3=FULL         2.0333
15
  2.0332
15
                       
MP4   2.2830
3
    2.0607
7
    2.0576
1
2.0614
3
        2.0599
6
         
B2PLYP         2.0674
15
                2.0360
15
         
B2PLYP=FULLultrafine         2.0703
11
                           
Configuration interaction CID   2.2692
3
2.0398
3
2.2447
3
2.0335
10
    2.0490
4
                     
CISD   2.2796
3
2.0430
3
2.2545
3
2.0349
10
    2.0518
3
                     
Quadratic configuration interaction QCISD   2.2935
15
2.0512
3
2.2818
3
2.0700
12
2.0579
3
2.0543
4
2.0635
7
2.0638
15
2.0459
3
    2.0807
4
2.0479
3
         
QCISD(T)         2.0605
4
    2.0605
1
        2.0887
3
2.0529
3
  2.0931
3
2.0504
3
   
Coupled Cluster CCD   2.2756
3
2.0434
3
2.2509
3
2.0549
15
2.0499
3
2.0469
3
2.0530
4
2.0533
3
2.0402
3
    2.0738
4
2.0425
3
  2.0795
3
2.0392
3
   
CCSD         2.0431
10
    2.0546
1
                     
CCSD(T)         2.0428
8
2.0515
1
  2.0594
1
    2.0305
1
  2.0836
4
2.0490
4
2.0147
1
2.0901
4
2.0477
4
   
CCSD(T)=FULL         2.0597
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 2.2111
15
2.0693
15
2.2106
15
2.0689
15
2.2141
15
2.2180
15
density functional B1B95 2.2389
12
2.0894
12
       
B3LYP 2.2555
15
2.1042
15
2.2523
15
2.1026
15
2.2561
15
2.2539
15
Moller Plesset perturbation MP2 2.2643
15
2.0773
15
2.2630
15
2.0759
15
2.2595
15
2.2637
15
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.