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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

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Calculated bond length in Å
Methods with predefined basis sets
semi-empirical AM1 1.233
PM3 1.216
PM6 1.209
composite G2 1.189
G3 1.189
G3B3 1.211
G4 1.205
CBS-Q 1.185

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 1.204 1.204 1.214 1.189 1.189 1.191 1.183 1.183 1.183 1.184 1.187 1.184 1.190 1.184
density functional LSDA 1.250 1.227 1.227 1.236 1.213 1.213 1.216 1.206 1.206 1.207 1.207 1.212 1.206 1.214 1.207
SVWN   1.227     1.213 1.213 1.216 1.206 1.206 1.207   1.212 1.206 1.214 1.207
BLYP 1.265 1.238 1.238 1.248 1.224 1.224 1.228 1.217 1.217 1.217 1.219 1.223 1.217    
B1B95 1.244 1.221 1.221 1.230 1.207 1.207 1.209 1.200 1.200 1.201 1.201 1.205 1.201 1.208 1.201
B3LYP 1.251 1.226 1.226 1.236 1.212 1.212 1.215 1.205 1.205 1.205 1.206 1.210 1.205 1.213 1.206
B3LYPultrafine         1.212             1.210 1.205 1.213 1.206
B3PW91 1.248 1.225 1.225 1.234 1.210 1.210 1.213 1.204 1.204 1.204 1.205 1.209 1.204    
mPW1PW91 1.244 1.223 1.223 1.232 1.208 1.208 1.210 1.201 1.201 1.202 1.202 1.206 1.202 1.209 1.202
M06-2X 1.237 1.222 1.222 1.228 1.205 1.206 1.208 1.199 1.199 1.200 1.201 1.204 1.200 1.207 1.201
PBEPBE 1.260 1.237 1.237 1.246 1.222 1.222 1.225 1.215 1.215 1.216 1.216 1.220 1.215 1.223 1.216
PBEPBEultrafine         1.222             1.220 1.215 1.223 1.217
PBE1PBE 1.244 1.223 1.223 1.232 1.208 1.208 1.211 1.202 1.202 1.203 1.203 1.207 1.202 1.209 1.203
HSEh1PBE 1.244 1.223 1.223 1.232 1.208 1.208 1.211 1.202 1.202 1.202 1.203 1.207 1.202 1.209 1.203
TPSSh         1.209   1.210           1.202    
Moller Plesset perturbation MP2 1.257 1.238 1.238 1.252 1.220 1.219 1.215 1.210 1.209 1.209 1.212 1.215 1.210 1.223  
MP2=FULL 1.257 1.238 1.238 1.252 1.219 1.218 1.222 1.209 1.209 1.207 1.211 1.215 1.207 1.222  
MP3         1.209   1.203                
MP3=FULL         1.203                    
MP4=FULL   1.244                          
B2PLYP         1.208                    
B2PLYP=FULLultrafine         1.208                    
Configuration interaction CID   1.217 1.217 1.230 1.200     1.192              
CISD   1.219 1.219 1.231 1.201     1.192              
Quadratic configuration interaction QCISD 1.260 1.233 1.233 1.247 1.216 1.215 1.219 1.206 1.205 1.204 1.207 1.212 1.205 1.218  
Coupled Cluster CCD 1.258 1.226 1.226 1.240 1.211 1.210 1.213 1.201 1.200 1.200 1.202 1.206 1.200 1.213  
CCSD         1.214                    
CCSD=FULL         1.213                    

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 1.229 1.201 1.226 1.195 1.219 1.219
density functional B1B95 1.240 1.217 1.237 1.210 1.230 1.230
B3LYP 1.254 1.226 1.251 1.219 1.243 1.243
Moller Plesset perturbation MP2 1.272 1.234 1.267 1.228 1.260 1.260
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
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