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IV.D.1. (XII.C.1.)

Geometry Comparison

C5H8 (Cyclobutane, methylene-)


distance is atom 1 (C) to atom 6 (H)

Experimental bond length is 1.101  Å

original data displayed. press to display differences
differences displayed. press to display original data
Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.101
PM6 1.096
composite G3 3.791
G3B3 1.096
CBS-Q 3.800
Calculated bond length in 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 aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF 1.088 1.081 1.081 1.083 1.084 1.084 1.084 1.084 1.084 1.084 1.082 1.083 1.091 1.082 1.089 1.082
density functional LSDA 1.104 1.102 1.102 1.103 1.104 1.103 1.103 1.102 1.101 1.102     1.109 1.099 1.106  
SVWN   1.102     1.104   1.103                  
BLYP 1.113 1.101 1.101 1.103 1.103 1.102 1.102 1.100 1.099 1.101     1.109 1.096 1.105  
B1B95 1.102 1.091 1.091 1.093 1.092 1.092 1.093 1.091 1.090 1.091     1.098 1.087 1.095  
B3LYP 1.104 1.093 1.093 1.096 1.096 1.095 1.095 1.093   1.094 1.090 1.091 1.101 1.090 1.098  
B3LYPultrafine         1.096                      
B3PW91   1.094 1.094 1.095 1.096 1.095 1.095 1.094   1.094     1.101 1.091 1.098  
mPW1PW91   1.092 1.092 1.093 1.094 1.093 1.093 1.092 1.091 1.092     1.099 1.089 1.096  
M06-2X         1.093                      
PBEPBE   1.102     1.104 1.102 1.103 1.101 1.101 1.102 1.099   1.109 1.099    
PBEPBEultrafine         1.104                      
HSEh1PBE         1.095                      
Moller Plesset perturbation MP2FC   1.094 1.094 1.099 1.094 1.090 1.090 1.093 1.093 1.090   1.090 1.102 1.088 1.100  
MP2FU   1.093 1.093 1.099 1.094 1.089 1.089 1.093         1.101 1.084    
MP3         1.094                      
B2PLYP         1.094   1.092                  
Configuration interaction CID   1.090     1.089                      
CISD   1.090     1.089                      
Quadratic configuration interaction QCISD   1.098 1.098 1.103 1.097 1.091 1.091 1.096         1.104      
Coupled Cluster CCD   1.097 1.097 1.102 1.096 1.090 1.090 1.095         1.103      
Calculated bond length in Å
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.087 1.089 1.085 1.086 1.082 1.082
density functional B1B95 1.100 1.100        
B3LYP 1.102 1.102 1.097 1.097 1.096 1.096
Moller Plesset perturbation MP2FC 1.111 1.103 1.103 1.095 1.104 1.104
Values that are outliers may reflect different atom numbering for different levels of theory.
Please use the error report form to report problems.