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III.G.1.a.

Comparison of levels of theory for F-H


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 1.1511
2
PM3 1.0994
4
PM6 1.0749
8
composite G2 1.0803
8
G3 1.0803
8
G3B3 1.1130
8
CBS-Q 1.0802
8
molecular mechanics DREIDING 0.9310
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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pCVDZ cc-pCVTZ cc-pCVQZ
hartree fock HF 1.0618
10
1.1024
8
1.1024
8
1.0952
8
1.0803
8
1.0692
8
1.2400
8
1.0589
8
1.0548
8
1.0314
10
0.8970
2
1.0249
10
1.0700
8
1.0612
8
1.0031
6
0.9896
7
0.9684
9
0.9742
7
0.9014
1
0.8980
1
0.8969
1
ROHF   1.1454
2
1.1454
2
1.1437
2
1.2288
4
1.1221
2
1.1339
2
1.1301
2
1.1178
2
    1.1232
2
1.1277
2
1.1216
2
1.1219
2
1.1285
2
1.1228
2
1.1222
2
     
density functional LSDA 1.1457
8
1.1525
8
1.1525
8
1.1243
8
1.1068
8
1.0969
8
1.1081
8
1.0680
8
1.0422
8
1.0905
8
  1.1470
2
1.0903
8
1.0469
8
  1.0175
8
1.0753
3
       
SVWN   1.1524
8
    1.1157
7
1.1472
2
1.1081
8
1.1580
2
1.1440
2
1.1389
2
    1.1527
2
1.1459
2
  1.1518
2
1.1468
2
       
BLYP 1.1395
10
1.1886
8
1.1886
8
1.1620
8
1.1436
8
1.1301
8
1.1347
8
1.1151
8
1.1055
8
1.0854
10
  1.1664
2
1.1301
8
1.0967
8
  0.9367
2
         
B1B95 1.1815
6
1.1941
6
1.1941
6
1.1682
6
1.1498
6
1.1432
6
1.1617
6
1.1226
6
1.1112
6
1.1341
6
  1.1440
2
1.1384
6
1.1012
6
1.0466
2
1.0308
5
1.0544
4
1.0084
1
     
B3LYP 1.1145
10
1.1547
8
1.1547
8
1.1289
8
1.1130
8
1.1022
8
1.1159
8
1.0884
8
1.1026
7
1.2767
10
0.9247
4
1.0388
10
1.1020
8
1.0736
8
1.0471
6
1.0173
7
1.0145
7
1.0015
7
0.9270
1
0.9227
1
 
B3LYPultrafine         1.1130
8
                               
B3PW91 1.1618
7
1.1469
8
1.1469
8
1.1208
8
1.1050
8
1.0941
8
1.1086
8
1.0766
8
1.0860
7
1.0556
10
  1.1465
2
1.0929
8
1.0596
8
  0.9233
2
         
mPW1PW91 1.1553
7
1.1391
8
1.1645
7
1.1144
8
1.0988
8
1.0877
8
1.1051
8
1.0706
8
1.0578
8
1.0502
10
  1.1425
2
1.0866
8
1.0541
8
  1.0345
4
1.0678
3
       
M06-2X 1.1472
2
1.1698
2
1.1698
2
1.1611
2
1.0956
8
1.1406
2
1.1422
2
1.1487
2
1.1374
2
1.1353
2
  1.1410
2
1.1462
2
1.1401
2
  1.1454
2
1.1411
2
       
PBEPBE 1.1851
7
1.1404
10
1.2028
7
1.1705
7
1.0916
10
1.0801
10
1.0871
10
1.0634
10
1.0818
8
1.0738
10
0.9330
4
1.1602
2
1.0790
10
1.0464
10
1.0818
2
1.0886
3
1.0458
4
1.0228
1
     
PBEPBEultrafine         0.9469
4
                               
HSEh1PBE 1.1631
2
1.1761
2
1.1761
2
1.1668
2
1.1000
8
1.1435
2
1.1451
2
1.1534
2
1.1401
2
1.1364
2
  1.1440
2
1.1497
2
1.1425
2
  1.1492
2
1.1435
2
       
Moller Plesset perturbation MP2FC 1.0430
6
1.1235
8
1.1235
8
1.1196
8
1.1012
8
1.0815
8
1.1477
8
1.0719
8
1.0174
8
1.0989
7
0.9179
1
1.0125
10
1.0737
8
1.0408
8
1.0328
6
1.0067
8
1.0265
5
1.0098
6
0.9198
1
0.9181
1
0.9173
1
MP2FU 1.0430
6
1.1234
8
1.1469
7
1.1442
7
1.1010
8
1.0812
8
1.1473
8
1.0716
8
1.0317
7
1.0984
7
  1.1422
2
1.0735
8
1.0372
8
1.0315
6
0.9965
8
1.0306
4
1.0233
5
0.9195
1
0.9176
1
0.9167
1
MP3         1.0952
8
                               
MP4   1.1231
8
    1.0988
8
    0.9181
2
1.0337
7
        1.0411
8
             
B2PLYP 1.1521
2
1.1747
2
1.1747
2
1.1704
2
1.1015
8
1.1439
2
1.1177
8
1.1543
2
1.1388
2
1.1370
2
  1.1454
2
1.1487
2
1.1431
2
  1.1536
2
1.1465
2
       
Configuration interaction CID   1.1418
7
1.1418
7
1.1366
7
1.0941
8
    1.0632
8
          0.9114
2
             
CISD   1.1206
8
1.1436
7
1.1395
7
1.0953
8
    1.0856
7
          0.9125
2
             
Quadratic configuration interaction QCISD   1.1231
8
1.1214
8
1.1443
7
1.0991
8
1.0795
8
1.0922
10
1.0686
8
1.0185
8
1.0956
7
  1.1372
2
1.0619
8
1.0702
6
  1.0740
3
1.0643
3
       
QCISD(T)         1.0989
8
0.9210
2
0.9254
2
0.9182
2
      1.1394
2
1.1074
6
1.0702
6
  1.0657
4
1.0564
4
       
Coupled Cluster CCD   1.1209
8
1.1438
7
1.1391
7
1.0966
8
1.0768
8
1.1353
8
1.0663
8
1.0291
7
1.0933
7
  1.1351
2
1.1042
6
1.0628
6
  1.0550
4
1.0466
4
       
CCSD         1.0395
5
0.9202
2
0.9240
2
0.9167
2
        1.0654
3
1.0600
3
             
CCSD(T)   0.9634
1
    1.1573
5
0.9209
2
0.9252
2
0.9181
2
0.9126
1
  0.9171
2
1.1391
2
1.1074
6
1.0699
6
1.0306
6
1.0182
6
1.0110
6
1.0084
6
0.9196
1
0.9170
1
0.9164
1
CCSD(T)=FULL         1.0398
5
            1.1388
2
1.0296
4
1.0244
4
1.0293
6
1.0378
4
1.0284
4
1.0072
6
0.9193
1
0.9165
1
0.9158
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 1.2174
8
1.2052
8
1.0840
8
1.0581
8
1.1614
8
1.1619
8
density functional B1B95 0.9445
2
0.9292
2
0.9393
1
0.9251
1
0.9443
1
0.9444
1
B3LYP 1.1230
8
1.1103
8
1.0946
8
1.0696
8
1.1238
8
1.1237
8
Moller Plesset perturbation MP2FC 1.1468
8
1.1270
8
1.1028
8
1.0661
8
1.1390
8
1.1391
8
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.