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III.G.1.a.

Comparison of levels of theory for S-Be


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 1.8712
2
PM3 1.7646
3
PM6 1.8316
3
composite G2 1.7981
3
G3 1.7981
3
G3B3 1.8075
3
CBS-Q 1.8001
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 1.7464
2		 1.8282
3		 1.8062
3		 1.8354
3		 1.7981
3		 1.7981
3		 1.7972
3		 1.7941
3		 1.7941
3		 1.7962
3		 1.7251
1		 1.8070
3		 1.7994
3		 1.8236
2		 1.7249
1		 1.8344
2		 1.7933
3		 1.7675
2		 1.7264
1
ROHF         1.8393
1		                            
density functional LSDA 1.7380
3		 1.8143
3		 1.8099
3		 1.8329
3		 1.8029
3		 1.8029
3		 1.8004
3		 1.7931
3		 1.7931
3		 1.7990
3		     1.8064
3		 1.7903
3		   1.8040
3		 1.8169
2		    
SVWN   1.8256
3		     1.8028
3		   1.8004
3		                        
BLYP 1.7824
2		 1.8448
3		 1.8283
3		 1.8534
3		 1.8227
3		 1.8227
3		 1.8206
3		 1.8143
3		 1.8143
3		 1.8191
3		     1.8245
3		 1.8373
2		   1.7680
1		      
B1B95 1.7352
3		 1.8150
3		 1.8099
3		 1.8346
3		 1.8019
3		 1.8027
3		 1.8007
3		 1.7964
3		 1.7964
3		 1.8004
3		     1.8060
3		 1.7927
3		   1.8047
3		      
B3LYP 1.7388
3		 1.8316
3		 1.8139
3		 1.8397
3		 1.8077
3		 1.8077
3		 1.8056
3		 1.8004
3		 1.8291
2		 1.8043
3		 1.7388
1		 1.8157
3		 1.8095
3		 1.8249
2		 1.7375
1		 1.8378
2		 1.7979
3		 1.7379
1		 1.7396
1
B3LYPultrafine         1.8078
3		                            
B3PW91 1.7661
2		 1.8315
3		 1.8139
3		 1.8379
3		 1.8051
3		 1.8051
3		 1.8035
3		 1.7993
3		 1.8280
2		 1.8023
3		     1.8362
2		 1.8244
2		   1.7507
1		      
mPW1PW91 1.7295
3		 1.8291
3		 1.8413
2		 1.8354
3		 1.8026
3		 1.8026
3		 1.8008
3		 1.7969
3		 1.7969
3		 1.8003
3		     1.8341
2		 1.8225
2		   1.7478
1		      
M06-2X         1.7983
3		                            
PBEPBE 1.7773
2		 1.8419
3		 1.8544
2		 1.8790
2		 1.8176
3		 1.8176
3		 1.8152
3		 1.8107
3		 1.8107
3		 1.8146
3		 1.7514
1		   1.8208
3		 1.8075
3		         1.7521
1
PBEPBEultrafine         1.7624
1		                            
HSEh1PBE         1.8038
3		                            
Moller Plesset perturbation MP2FC 1.7613
2		 1.8479
3		 1.8208
3		 1.8561
3		 1.8032
3		 1.8032
3		 1.8025
3		 1.8018
3		 1.8018
3		 1.8095
3		   1.8226
3		 1.8186
3		 1.8327
2		 1.7524
1		 1.8269
3		 1.8110
3		 1.7533
1		 1.7573
1
MP2FU 1.7609
2		 1.8478
3		 1.8459
2		 1.8836
2		 1.7994
3		 1.7994
3		 1.7986
3		 1.8003
3		 1.8249
2		 1.8258
2		     1.8402
2		 1.8209
2		 1.7438
1		 1.7726
1		     1.7456
1
MP3         1.7956
3		                            
MP4   1.8847
2		     1.8119
3		     1.7683
1		 1.8321
2		         1.8150
3		          
B2PLYP         1.8066
3		   1.8052
3		                        
Configuration interaction CID   1.8724
2		 1.8427
2		 1.8831
2		 1.7955
3		     1.7941
3		                      
CISD   1.8783
2		 1.8467
2		 1.8890
2		 1.7997
3		     1.8256
2		                      
Quadratic configuration interaction QCISD   1.8585
3		 1.8525
2		 1.8964
2		 1.8068
3		 1.8317
2		 1.8059
3		 1.8056
3		 1.8057
3		 1.8360
2		     1.8218
3		 1.8063
3		         1.7518
1
QCISD(T)         1.8119
3		     1.7636
1		         1.8520
2		 1.8375
2		   1.8600
2		 1.8410
2		    
Coupled Cluster CCD   1.8742
2		 1.8445
2		 1.8851
2		 1.7975
3		 1.8248
2		 1.8234
2		 1.7964
3		 1.8238
2		 1.8313
2		     1.8129
3		 1.8279
2		   1.8491
2		 1.8314
2		    
CCSD         1.8021
3		     1.7470
1		                      
CCSD(T)   1.8008
1		     1.7598
1		 1.7598
1		 1.7598
1		 1.7588
1		 1.7588
1		   1.7570
1		   1.8257
3		 1.8112
3		   1.8324
3		 1.8139
3		   1.7595
1
CCSD(T)=FULL         1.8300
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 1.8435
3		 1.8069
3		 1.8377
3		 1.7968
3		 1.8416
3		 1.8304
3
density functional B1B95 1.7925
1		 1.7702
1		        
B3LYP 1.8598
3		 1.8249
3		 1.8534
3		 1.8154
3		 1.8538
3		 1.8353
3
Moller Plesset perturbation MP2FC 1.8781
3		 1.8241
3		 1.8597
3		 1.8102
3		 1.8618
3		 1.8469
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.