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III.G.1.a.

Comparison of levels of theory for H-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 1.4365
4
PM3 1.3252
6
PM6 1.7086
6
composite G2 1.7806
5
G3 1.6949
6
G3B3 1.4697
6
CBS-Q 1.7806
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(D+d)Z cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ
hartree fock HF 1.5386
6		 1.6647
6		 1.6466
6		 1.7228
6		 1.2798
5		 1.6735
6		 1.9156
6		 1.7739
6		 1.6845
6		 1.6744
6		 1.2640
2		 1.6298
6		 1.5729
6		 1.5828
6		 1.2841
5		 1.2977
6		 1.2858
6		 1.2842
5		 1.2725
1		 1.6430
5		 1.3026
2		 1.2925
2		 1.2819
1
ROHF         1.2936
1		                                    
density functional LSDA 1.5184
6		 1.4709
6		 1.4609
6		 1.4924
6		 1.4560
6		 1.4515
6		 1.4404
6		 1.4493
6		 1.4387
6		 1.4489
6		     1.4499
6		 1.4328
6		 1.3302
3		 1.3436
6		 1.3328
5		 1.3303
3		 1.2989
1		        
SVWN   1.4934
6		     1.3114
4		   1.4404
6		                                
BLYP 1.5393
6		 1.5221
6		 1.4925
6		 1.5254
6		 1.4897
6		 1.4831
6		 1.4776
6		 1.4790
6		 1.4695
6		 1.4825
6		     1.4840
6		 1.4650
6		   1.3053
2		     1.3024
1		        
B1B95 1.5191
6		 1.4794
6		 1.4704
6		 1.4999
6		 1.4653
6		 1.4602
6		 1.4631
6		 1.4623
6		 1.4532
6		 1.4600
6		     1.4589
6		 1.4454
6		 1.3124
3		 1.3194
6		 1.3160
4		 1.3124
3		 1.2844
1		        
B3LYP 1.5212
6		 1.5017
6		 1.4728
6		 1.5037
6		 1.4697
6		 1.4644
6		 1.4646
6		 1.4650
6		 1.5405
4		 1.4637
6		 1.2801
2		 1.4550
6		 1.4639
6		 1.4493
6		 1.3031
5		 1.3312
6		 1.3120
6		 1.3032
5		 1.2916
1		 1.4789
5		 1.3257
2		 1.3127
2		 1.2983
1
B3LYPultrafine         1.4691
6		                                    
B3PW91 1.6101
4		 1.4941
6		 1.4653
6		 1.4945
6		 1.4604
6		 1.4551
6		 1.4560
6		 1.4574
6		 1.5281
4		 1.4540
6		     1.4529
6		 1.4394
6		   1.2922
2		     1.2880
1		        
mPW1PW91 1.6059
4		 1.4911
6		 1.4984
5		 1.4916
6		 1.4577
6		 1.4525
6		 1.4554
6		 1.4562
6		 1.4452
6		 1.4511
6		     1.4493
6		 1.4369
6		   1.2899
2		     1.2856
1		        
M06-2X         1.4679
6		                           1.2862
1		        
PBEPBE 1.5692
5		 1.5068
6		 1.5128
5		 1.5439
5		 1.4725
6		 1.4663
6		 1.4629
6		 1.4656
6		 1.4542
6		 1.4652
6		 1.2874
2		   1.4638
6		 1.4476
6		 1.3264
3		 1.3016
1		 1.2912
2		 1.3266
3		 1.2981
1		 1.2883
1		     1.3055
1
PBEPBEultrafine         1.2967
2		                                    
HSEh1PBE         1.4596
6		                           1.2866
1		        
Moller Plesset perturbation MP2FC 1.3902
3		 1.6331
6		 1.5964
6		 1.6752
6		 1.6107
6		 1.5338
6		 1.8997
6		 1.6284
6		 1.5226
6		 1.5486
6		   1.4673
6		 1.4689
6		 1.4523
6		 1.2927
5		 1.3129
6		 1.2966
6		 1.2984
4		 1.2803
1		 1.4852
5		 1.3034
3		 1.2912
3		 1.2976
1
MP2FU 1.3901
3		 1.6313
6		 1.7508
4		 1.8486
4		 1.6047
6		 1.5293
6		 1.8844
6		 1.6247
6		 1.6438
4		 1.6768
4		     1.4670
6		 1.5366
4		 1.2913
5		 1.2867
2		 1.2710
1		 1.3053
3		 1.2785
1		 1.4803
5		 1.3024
3		 1.2897
3		  
MP3         1.6063
6		                                    
MP4   1.6279
6		     1.5876
6		     1.2903
2		 1.5595
4		         1.5035
4		         1.2836
1		        
B2PLYP         1.4744
6		   1.4719
6		                       1.2858
1		        
Configuration interaction CID   1.7935
4		 1.7619
4		 1.8567
4		 1.6193
6		     1.6182
6		           1.2722
2		                  
CISD   1.6199
6		 1.7483
4		 1.8039
4		 1.5968
6		     1.7505
4		           1.2727
2		                  
Quadratic configuration interaction QCISD   1.6129
6		 1.5926
6		 1.7790
4		 1.5698
6		 1.5030
6		 1.8860
6		 1.5618
6		 1.4970
5		 1.6418
4		     1.4573
6		 1.4411
6		         1.2836
1		 1.2924
3		 1.3147
2		 1.3020
2		  
QCISD(T)         1.5636
6		 1.2734
2		 1.2743
2		 1.2919
2		         1.4559
6		 1.4391
6		   1.3296
4		 1.3120
4		            
Coupled Cluster CCD   1.6338
6		 1.7509
4		 1.8507
4		 1.6050
6		 1.5207
6		 1.8969
6		 1.5995
6		 1.5661
4		 1.6678
4		     1.4565
6		 1.4407
6		   1.3253
4		 1.3074
4		   1.2829
1		 1.3016
2		 1.3140
2		 1.3015
2		  
CCSD         1.7022
4		 1.2724
2		 1.2731
2		 1.2898
2		         1.2892
2		 1.2755
2		                  
CCSD(T)   1.3235
1		     1.6133
5		 1.2734
2		 1.2743
2		 1.2919
2		 1.2776
1		   1.2768
2		   1.4558
6		 1.4390
6		 1.3170
1		 1.3221
5		 1.3053
5		 1.3175
1		 1.2848
1		 1.4682
5		 1.3070
3		 1.2942
3		  
CCSD(T)=FULL         1.3044
4		               1.3063
3		 1.2950
3		 1.3155
1		 1.3098
3		 1.2948
3		 1.3159
1		 1.2830
1		 1.3019
2		 1.3058
3		 1.2929
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 1.7710
6		 1.7481
6		 1.7045
6		 1.6746
6		 1.6350
6		 1.6395
6
density functional B1B95 1.3246
2		 1.2969
2		 1.3299
1		 1.2967
1		 1.3123
1		 1.3118
1
B3LYP 1.5252
6		 1.4926
6		 1.4998
6		 1.4610
6		 1.4981
6		 1.4996
6
Moller Plesset perturbation MP2FC 1.7515
6		 1.7167
6		 1.6377
6		 1.5638
6		 1.5998
6		 1.6054
6
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.