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

Geometry Comparison

C4H8O2 (Ethyl acetate)


distance is atom 1 (O) to atom 2 (C)

Experimental bond length is 1.203  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 AM1 1.232
PM3 1.213
PM6 1.204
composite G2 1.184
G3 1.184
G3B3 1.207
CBS-Q 1.180

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) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF 1.216 1.199 1.199 1.207 1.184 1.184 1.186 1.178 1.178 1.178 1.179 1.182 1.179 1.186 1.180
density functional SVWN   1.217     1.208   1.207                
BLYP 1.265 1.233 1.233 1.242 1.219 1.219 1.223 1.212 1.212 1.213   1.217 1.212    
B1B95 1.246 1.217 1.217 1.225 1.203 1.203 1.206 1.196 1.197     1.202 1.197    
B3LYP 1.251 1.221 1.221 1.229 1.207 1.207 1.210 1.200 1.200 1.201 1.199 1.205 1.200 1.209 1.202
B3LYPultrafine         1.207                    
B3PW91 1.248 1.220 1.220 1.228 1.206 1.206 1.208 1.199 1.199 1.200   1.204 1.199    
mPW1PW91 1.245 1.218 1.218 1.225 1.203 1.203 1.206 1.196 1.197 1.198   1.201 1.197    
M06-2X         1.200                    
PBEPBE 1.260 1.232 1.232 1.239 1.217 1.217 1.220 1.210 1.210 1.211   1.215 1.211 1.219 1.212
PBEPBEultrafine         1.217                    
HSEh1PBE         1.202                    
Moller Plesset perturbation MP2FC 1.259 1.235 1.235 1.246 1.215 1.215 1.219 1.206 1.205 1.205 1.204 1.211 1.206 1.218  
MP2FU 1.259 1.234 1.234 1.246 1.215 1.214 1.218 1.205 1.204 1.202   1.211 1.203    
MP3         1.204                    
B2PLYP         1.208   1.210                
Configuration interaction CID   1.213 1.213 1.223 1.196                    
CISD   1.214 1.214 1.224 1.197     1.188              
Quadratic configuration interaction QCISD 1.260 1.229 1.229 1.241 1.211 1.211 1.214 1.202 1.201     1.207      
Coupled Cluster CCD 1.258 1.223 1.223 1.234 1.206 1.206 1.209 1.196 1.196     1.202      

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 1.221 1.197 1.219 1.191 1.212 1.212
density functional B1B95 1.240 1.217 1.237 1.210 1.230 1.230
B3LYP 1.247 1.221 1.244 1.215 1.236 1.236
Moller Plesset perturbation MP2FC 1.265 1.230 1.259 1.223 1.253 1.253
Values that are outliers may reflect different atom numbering for different levels of theory.
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