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III.G.1.a.

Comparison of levels of theory for Be-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 1.8909
2
PM3 1.7565
3
PM6 1.8764
3
composite G2 1.8644
3
G3 1.8644
3
G3B3 1.8611
3
CBS-Q 1.8709
3
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 1.8449
3		 1.9217
3		 1.8904
3		 1.9367
3		 1.8643
3		 1.8644
3		 1.8258
3		 1.8427
3		 1.8432
3		 1.8638
3		 1.8084
1		 1.8521
3		 1.8549
3		 1.8391
2		 1.8258
3		 1.8463
2		 1.8251
3		 1.8201
3		 1.8293
3
ROHF   1.8625
1		 1.8377
1		   1.8171
1		 1.8171
1		 1.8150
1		 1.8158
1		                      
density functional LSDA 1.8331
3		 1.8643
3		 1.8584
3		 1.8892
3		 1.8418
3		 1.8418
3		 1.8093
3		 1.8164
3		 1.8164
3		 1.8395
3		     1.8336
3		 1.8062
3		 1.7085
1		 1.8175
3		 1.8060
2		 1.7086
1		  
SVWN   1.8768
3		     1.8418
3		   1.8093
3		                        
BLYP 1.8587
3		 1.9076
3		 1.8870
3		 1.9256
3		 1.8747
3		 1.8747
3		 1.8359
3		 1.8478
3		 1.8479
3		 1.8723
3		     1.8606
3		 1.8430
2		   1.8280
1		      
B1B95 1.8485
3		 1.8825
3		 1.8758
3		 1.9113
3		 1.8579
3		 1.8585
3		 1.8225
3		 1.8355
3		 1.8355
3		 1.8571
3		     1.8480
3		 1.8331
2		 1.7121
1		 1.8320
3		 1.8244
2		 1.7122
1		  
B3LYP 1.8482
3		 1.8984
3		 1.8761
3		 1.9146
3		 1.8611
3		 1.8611
3		 1.8252
3		 1.8365
3		 1.8501
2		 1.8592
3		 1.8019
1		 1.8496
3		 1.8496
3		 1.8326
2		 1.8193
3		 1.8407
2		 1.8190
3		 1.8136
3		 1.8225
3
B3LYPultrafine         1.8612
3		                            
B3PW91 1.8731
2		 1.9003
3		 1.8779
3		 1.9130
3		 1.8583
3		 1.8583
3		 1.8244
3		 1.8356
3		 1.8492
2		 1.8568
3		     1.8653
2		 1.8338
2		   1.8180
1		      
mPW1PW91 1.8699
2		 1.8976
3		 1.8979
2		 1.9103
3		 1.8551
3		 1.8551
3		 1.8217
3		 1.8327
3		 1.8329
3		 1.8538
3		     1.8620
2		 1.8310
2		   1.8169
1		      
M06-2X         1.8590
3		                            
PBEPBE 1.8781
2		 1.9027
3		 1.9060
2		 1.9464
2		 1.8655
3		 1.8655
3		 1.8298
3		 1.8418
3		 1.8418
3		 1.8636
3		 1.8061
1		   1.8553
3		 1.8290
3		 1.7218
1		     1.7219
1		  
PBEPBEultrafine         1.8179
1		                            
HSEh1PBE         1.8549
3		                            
Moller Plesset perturbation MP2FC 1.8687
2		 1.9218
3		 1.8770
3		 1.9399
3		 1.8351
3		 1.8351
3		 1.8044
3		 1.8239
3		 1.8241
3		 1.8542
3		   1.8455
3		 1.8450
3		 1.8361
2		 1.8057
1		 1.8448
3		 1.8258
3		 1.8068
1		 1.8268
3
MP2FU 1.8685
2		 1.9217
3		 1.8993
2		 1.9755
2		 1.8309
3		 1.8309
3		 1.8005
3		 1.8212
3		 1.8317
2		 1.8642
2		     1.8555
2		 1.8214
2		 1.7956
1		 1.8269
1		     1.8120
3
MP3         1.8340
3		                            
MP4   1.9600
2		     1.8378
3		     1.8040
1		 1.8407
2		         1.8129
1		          
B2PLYP         1.8494
3		   1.8157
3		                        
Configuration interaction CID   1.9587
2		 1.9056
2		 1.9877
2		 1.8387
3		     1.8268
3		                      
CISD   1.9604
2		 1.9073
2		 1.9894
2		 1.8397
3		     1.8403
2		                      
Quadratic configuration interaction QCISD   1.9322
3		 1.9110
2		 1.9951
2		 1.8406
3		 1.8608
2		 1.8099
3		 1.8300
3		 1.8302
3		 1.8827
2		     1.8515
3		 1.8331
3		          
QCISD(T)         1.8397
3		     1.8053
1		         1.8665
2		 1.8438
2		   1.8633
2		 1.8402
2		    
Coupled Cluster CCD   1.9611
2		 1.9081
2		 1.9917
2		 1.8391
3		 1.8593
2		 1.8131
2		 1.8280
3		 1.8411
2		 1.8814
2		     1.8494
3		 1.8425
2		   1.8597
2		 1.8369
2		    
CCSD         1.8401
3		     1.8036
1		                      
CCSD(T)         1.8007
1		 1.8007
1		   1.8049
1		     1.8071
1		   1.8509
3		 1.8333
3		   1.8527
3		 1.8319
3		    
CCSD(T)=FULL         1.8539
2		                            
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 1.9157
3		 1.8464
3		 1.9070
3		 1.8392
3		 1.9236
3		 1.9238
3
density functional B1B95 1.8708
1		 1.8249
1		        
B3LYP 1.9169
3		 1.8560
3		 1.9060
3		 1.8481
3		 1.9147
3		 1.9100
3
Moller Plesset perturbation MP2FC 1.9277
3		 1.8421
3		 1.9117
3		 1.8294
3		 1.9199
3		 1.9228
3
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.