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

Geometry Comparison

C3H4 (cyclopropene)


distance is atom 2 (C) to atom 4 (H)

Experimental bond length is 1.072  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 1.073
PM6 1.046
composite G2 1.068
G3 1.068
G3B3 1.080
CBS-Q 2.247

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF 1.075 1.058 1.058 1.061 1.068 1.068 1.068 1.068 1.067 1.066 1.066 1.066 1.075 1.065 1.065 1.073 1.065
density functional LSDA 1.093 1.081 1.081 1.084 1.089 1.088 1.088 1.087 1.085 1.085     1.095 1.084   1.093  
SVWN   1.081     1.089   1.088                    
BLYP 1.100 1.080 1.080 1.083 1.087 1.086 1.086 1.085 1.083 1.082     1.093 1.081   1.091  
B1B95 1.090 1.070 1.070 1.074 1.078 1.077 1.077 1.077 1.075 1.075     1.084 1.073   1.081  
B3LYP 1.092 1.072 1.072 1.075 1.080 1.079 1.079 1.078   1.076 1.075 1.075 1.086 2.309   1.084 1.074
B3LYPultrafine         1.080   1.079                    
B3PW91   1.072 1.072 1.075 1.080 1.079 1.079 1.079   1.077     1.086 1.076   1.084  
mPW1PW91   1.071   1.073 1.078 1.077 1.077 1.077 1.076 1.075     1.084 1.074   1.082  
M06-2X         1.078                        
PBEPBE   1.081     1.088 1.087 1.087 1.087 1.085 1.084 1.083   1.094 1.083     2.264
PBEPBEultrafine         1.088                        
HSEh1PBE         1.079                        
Moller Plesset perturbation MP2FC   1.072 1.072 1.079 1.079 1.074 1.075 1.078 1.077 1.074   1.074 1.088 1.073   1.086  
MP2FU   1.072     2.311 1.073 2.307 1.078         1.087        
MP3         1.078                        
MP4   1.077 1.077 1.083 1.082                        
B2PLYP         1.078   1.076                    
Configuration interaction CID         2.307                        
CISD         2.308                        
Quadratic configuration interaction QCISD   1.076 1.076 1.082 1.080 1.074 1.075 1.080 1.078       1.089        
QCISD(T)         2.325                        
Coupled Cluster CCD   1.075 1.075 1.082 1.080 1.074 1.074 1.079         1.089 1.073      
CCSD         2.319                        
CCSD(T)         1.082 2.318                      

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 1.069 1.075 1.066 1.071 1.062 1.062
density functional B1B95 1.083 1.088        
B3LYP 1.085 1.089 1.080 1.084 1.077 1.077
Moller Plesset perturbation MP2FC 1.091 1.090 1.084 1.082 1.083 1.083
Values that are outliers may reflect different atom numbering for different levels of theory.
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