return to home page

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

Geometry Comparison

CH2CO (Ketene)


distance is atom 2 (C) to atom 3 (O)

Experimental bond length is 1.162  Å

Display Options
Switch to bar chart display
Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.175
PM6 1.165
composite G2 1.145
G3 1.145
G3B3 1.171
G4 1.160
CBS-Q 1.140

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 1.183 1.162 1.162 1.167 1.145 1.145 1.144 1.136 1.136 1.137 1.134 1.135 1.141 1.135 1.133 1.141 1.135
density functional LSDA 1.221 1.187 1.187 1.193 1.173 1.173 1.173 1.163 1.163 1.166     1.171 1.162   1.170  
SVWN   1.187     1.173   1.173                    
BLYP 1.236 1.199 1.199 1.206 1.185 1.185 1.185 1.175 1.175 1.177     1.182 1.173   1.181  
B1B95 1.215 1.183 1.183 1.188 1.166 1.167 1.167 1.158 1.158 1.160     1.164 1.155   1.162  
B3LYP 1.219 1.186 1.186 1.192 1.171 1.171 1.171 1.162   1.163 1.159 1.161 1.168 1.160   1.168 1.160
B3LYPultrafine         1.171   1.171             1.160     1.157
B3PW91   1.186 1.186 1.191 1.170 1.169 1.169 1.160   1.162     1.167 1.159   1.166  
mPW1PW91   1.183   1.188 1.167 1.167 1.166 1.158 1.157 1.159     1.164 1.156   1.164  
M06-2X         1.164                        
PBEPBE   1.197     1.182 1.182 1.182 1.173 1.173 1.175 1.170   1.179 1.172     1.171
PBEPBEultrafine         1.182                        
PBE1PBE         1.167                        
HSEh1PBE         1.167                        
TPSSh         1.170   1.169             1.160      
Moller Plesset perturbation MP2   1.198 1.198 1.207 1.175 1.180 1.181 1.169 1.168 1.168   1.168 1.176 1.163   1.179  
MP2=FULL   1.197     1.174 1.179 1.180 1.168         1.175 1.161      
MP3         1.169   1.165                    
MP3=FULL         1.165   1.164                    
MP4         1.189                        
B2PLYP         1.175                 1.160      
B2PLYP=FULLultrafine         1.175                        
Configuration interaction CID         1.164                        
CISD         1.166                        
Quadratic configuration interaction QCISD   1.197     1.178   1.178 1.165 1.164       1.173        
QCISD(T)         1.182                        
Coupled Cluster CCD         1.172               1.166        
CCSD         1.175                        
CCSD(T)         1.181 1.180                      

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 1.180 1.156 1.177 1.149 1.171 1.171
density functional B1B95 1.203 1.181        
B3LYP 1.209 1.184 1.205 1.177 1.198 1.198
Moller Plesset perturbation MP2 1.227 1.194 1.220 1.186 1.215 1.215
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
Please use the error report form to report problems.