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

Geometry Comparison

CH3OC2H5 (Ethane, methoxy-)


distance is atom 5 (C) to atom 8 (O)

Experimental bond length is 1.412  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 1.423
PM6 1.452
composite G2 1.396
G3 1.396
CBS-Q 1.396

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 1.437 1.437 1.437 1.429 1.396 1.397   1.395 1.396 1.393 1.392 1.396 1.396 1.393 1.400 1.394
density functional LSDA 1.458 1.437 1.437 1.432 1.397 1.397 1.401 1.396 1.397 1.392     1.396 1.396 1.402  
SVWN   1.437     1.397   1.402                  
BLYP 1.497 1.476 1.476 1.474   1.435 1.441 1.435 1.436 1.428     1.433 1.435 1.441  
B3LYP 1.475 1.458 1.458 1.453   1.417 1.421 1.417   1.412 1.415 1.419   1.416    
B3PW91   1.453 1.453 1.447   1.411 1.414 1.410   1.406     1.410 1.410 1.416  
mPW1PW91   1.449   1.444 1.407 1.408 1.411 1.406 1.407 1.403     1.406 1.406 1.412  
M06-2X         1.408                      
PBEPBE   1.467     1.422 1.422 1.427 1.422 1.424 1.418 1.422   1.421 1.422   1.425
PBEPBEultrafine         1.422                      
HSEh1PBE         1.407                      
Moller Plesset perturbation MP2FC   1.470 1.470 1.471   1.419 1.425 1.414 1.413     1.416 1.416   1.429  
MP2FU   1.469       1.418 1.423 1.413         1.415      
MP3         1.417                      
B2PLYP         1.417   1.422                  
Quadratic configuration interaction QCISD   1.469     1.420     1.414                

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 1.440 1.408 1.439 1.406 1.435 1.435
density functional B3LYP 1.469 1.433 1.466 1.431 1.460 1.459
Moller Plesset perturbation MP2FC 1.489 1.435 1.485 1.433 1.484 1.484
Values that are outliers may reflect different atom numbering for different levels of theory.
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