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You are here: Calculated > Geometry > Calculated geometry > One type of bond

Comparison of levels of theory for I-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 PM3 2.1924
1

average calculated bond lengths (Å)
Methods with standard basis sets
3-21G 3-21G* 6-31G* 6-311G*
hartree fock HF 2.4900
1
2.3581
1
  2.3477
1
density functional LSDA 2.4890
1
2.3522
1
  2.3520
1
BLYP 2.5566
1
2.4198
1
  2.4244
1
B1B95 2.4947
1
2.3571
1
  2.3534
1
B3LYP 2.5256
1
2.3905
1
  2.3900
1
B3LYPultrafine 2.5284
1
2.3892
1
  2.3910
1
B3PW91 2.5070
1
2.3695
1
  2.3659
1
mPW1PW91 2.4991
1
2.3623
1
  2.3580
1
M06-2X 2.4918
1
2.3562
1
  2.3571
1
PBEPBE 2.5269
1
2.3865
1
  2.3870
1
PBEPBEultrafine 2.5309
1
2.3848
1
  2.3882
1
PBE1PBE 2.4979
1
2.3602
1
  2.3562
1
HSEh1PBE 2.5035
1
2.3650
1
  2.3618
1
wB97X-D   2.3572
1
   
B97D3 2.5383
1
     
3-21G 3-21G* 6-31G* 6-311G*
Moller Plesset perturbation MP2 2.5426
1
2.3734
1
2.3721
1
2.3724
1
MP2=FULL 2.5429
1
2.3732
1
  2.3683
1
MP4 2.5641
1
2.3921
1
  2.3877
1
B2PLYP 2.5300
1
2.3823
1
  2.3798
1
Configuration interaction CID 2.5494
1
2.3746
1
  2.3627
1
CISD 2.5554
1
2.3766
1
  2.3643
1
3-21G 3-21G* 6-31G* 6-311G*
Quadratic configuration interaction QCISD 2.5676
1
2.3887
1
  2.3815
1
QCISD(T) 2.5724
1
2.3971
1
  2.3918
1
Coupled Cluster CCD 2.5588
1
2.3843
1
  2.3769
1
CCSD 2.5667
1
2.3885
1
  2.3810
1
CCSD(T) 2.5725
1
2.3971
1
  2.3917
1
CCSD(T)=FULL 2.5725
1
2.3968
1
  2.3925
1
3-21G 3-21G* 6-31G* 6-311G*

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 2.4418
1
  2.4428
1
  2.4609
1
2.4683
1
2.3172
1
  2.3092
1
ROHF             2.3172
1
  2.3092
1
density functional LSDA 2.4844
1
  2.4838
1
  2.5000
1
2.4969
1
2.3158
1
  2.3051
1
BLYP 2.5294
1
  2.5281
1
  2.5446
1
2.5483
1
2.3872
1
  2.3770
1
B1B95 2.4734
1
  2.4730
1
  2.4910
1
2.4897
1
2.3200
1
  2.3106
1
B3LYP 2.4970
1
  2.4962
1
  2.5128
1
2.5161
1
2.3552
1
  2.3450
1
B3LYPultrafine 2.4974
1
  2.4966
1
  2.5127
1
2.5163
1
2.3552
1
  2.3450
1
B3PW91 2.4788
1
  2.4777
1
  2.4958
1
2.4978
1
2.3315
1
  2.3217
1
mPW1PW91 2.4696
1
  2.4692
1
  2.4869
1
2.4895
1
2.3243
1
  2.3134
1
M06-2X 2.4609
1
  2.4616
1
  2.4771
1
2.4813
1
2.3243
1
  2.3156
1
PBEPBE 2.5007
1
  2.4995
1
  2.5165
1
2.5190
1
2.3504
1
  2.3404
1
PBEPBEultrafine 2.5017
1
  2.5005
1
  2.5168
1
2.5197
1
2.3504
1
  2.3404
1
PBE1PBE 2.4678
1
  2.4674
1
  2.4850
1
2.4879
1
2.3217
1
  2.3117
1
HSEh1PBE 2.4720
1
  2.4714
1
  2.4890
1
2.4919
1
2.3264
1
  2.3161
1
TPSSh             2.3371
1
  2.3277
1
wB97X-D             2.3241
1
  2.3145
1
B97D3             2.3649
1
  2.3542
1
Moller Plesset perturbation MP2 2.5056
1
  2.5058
1
  2.5164
1
2.5245
1
2.3188
1
  2.3068
1
MP2=FULL 2.5056
1
  2.5058
1
  2.5164
1
2.5256
1
2.3156
1
  2.3035
1
ROMP2             2.3183
1
  2.3068
1
MP3             2.3319
1
  2.3233
1
MP3=FULL             2.3296
1
  2.3209
1
MP4 2.5337
1
  2.5306
1
  2.5456
1
2.5509
1
2.3378
1
  2.3271
1
MP4=FULL             2.3349
1
  2.3239
1
B2PLYP 2.4969
1
  2.4968
1
  2.5117
1
2.5171
1
2.3403
1
  2.3299
1
B2PLYP=FULL             2.3395
1
  2.3290
1
B2PLYP=FULLultrafine             2.3395
1
  2.3290
1
Configuration interaction CID 2.5228
1
  2.5175
1
  2.5357
1
2.5381
1
2.3185
1
  2.3036
1
CISD 2.5298
1
  2.5236
1
  2.5432
1
2.5436
1
2.3200
1
  2.3043
1
Quadratic configuration interaction QCISD 2.5386
1
  2.5342
1
  2.5519
1
2.5548
1
2.3328
1
  2.3230
1
QCISD(T) 2.5419
1
  2.5380
1
  2.5561
1
2.5601
1
2.3409
1
  2.3307
1
QCISD(T)=FULL             2.3379
1
  2.3275
1
Coupled Cluster CCD 2.5295
1
  2.5257
1
  2.5424
1
2.5473
1
2.3299
1
  2.3191
1
CCSD 2.5379
1
  2.5333
1
  2.5514
1
2.5544
1
2.3326
1
  2.3224
1
CCSD=FULL             2.3296
1
  2.3187
1
CCSD(T) 2.5421
1
  2.5380
1
  2.5564
1
2.5602
1
2.3408
1
  2.3305
1
CCSD(T)=FULL 2.5421
1
  2.5380
1
  2.5564
1
2.5613
1
2.3379
1
  2.3274
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.