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

Geometry Comparison

CH3NC (methyl isocyanide)


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

Experimental bond length is 1.426  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 1.395
PM3 1.433
PM6 1.439
composite G3 1.421
CBS-Q 1.423

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 1.447 1.432 1.432 1.421 1.421 1.421 1.423 1.423 1.424 1.419 1.420 1.422 1.423 1.420 1.464 1.426 1.421
density functional LSDA 1.451 1.413 1.413 1.404 1.398 1.397 1.399 1.397 1.398 1.393     1.399 1.395   1.401  
SVWN   1.413     1.398   1.399                    
BLYP 1.486 1.449 1.449 1.438 1.430 1.430 1.433 1.431 1.432 1.425     1.431 1.429      
B1B95 1.458 1.429 1.429 1.418 1.412 1.412 1.414 1.413 1.414       1.413 1.411      
B3LYP 1.469 1.436 1.436 1.426 1.420 1.420 1.423 1.422 1.422 1.416   1.420 1.421 1.419   1.425 1.420
B3LYPultrafine         1.420                        
B3PW91 1.462 1.430 1.430 1.420 1.414 1.414 1.416 1.415 1.415 1.411     1.415 1.412      
mPW1PW91 1.458 1.428 1.428 1.418 1.412 1.412 1.414 1.413 1.413 1.409     1.413 1.410      
M06-2X         1.420                        
PBEPBE 1.472 1.438 1.438 1.427 1.420 1.419 1.421 1.420 1.421 1.416     1.420 1.418     1.418
HSEh1PBE         1.411                        
Moller Plesset perturbation MP2FC 1.477 1.457 1.457 1.449 1.426 1.424 1.427 1.425 1.425 1.418   1.423 1.427 1.420   1.433  
MP2FU 1.477 1.457 1.457 1.448 1.423 1.422 1.424 1.424 1.423 1.412     1.426 1.414      
MP3         1.426                        
MP4   1.460     1.430                        
B2PLYP         1.423   1.425                    
Configuration interaction CID   1.447 1.447 1.439 1.423     1.423                  
CISD   1.449 1.449 1.440 1.424     1.424                  
Quadratic configuration interaction QCISD 1.479 1.457 1.457 1.449 1.430 1.429 1.431 1.429 1.430 1.423     1.433 1.424      
QCISD(T)         1.432   1.433   1.432                
Coupled Cluster CCD 1.477 1.454 1.454 1.445 1.427 1.426 1.428 1.427 1.427 1.421     1.430 1.422      
CCSD(T)         1.432   1.434   1.432                

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 1.444 1.442 1.438 1.434 1.429 1.429
density functional B1B95 1.439 1.431        
B3LYP 1.453 1.445 1.445 1.436 1.431 1.432
Moller Plesset perturbation MP2FC 1.474 1.448 1.467 1.440 1.457 1.457
Values that are outliers may reflect different atom numbering for different levels of theory.
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