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

Geometry Comparison

C3H2N2 (Malononitrile)


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

Experimental bond length is 1.459  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 1.450
PM6 1.456
composite G2 1.472
G3 1.472
G3B3 1.470
CBS-Q 1.473

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 1.492 1.461 1.461 1.463 1.472 1.471 1.472 1.469 1.469 1.470 1.468 1.468 1.471 1.468 1.473 1.468
density functional LSDA 1.487 1.448 1.448 1.451 1.451 1.451 1.451 1.445 1.445 1.447     1.451 1.444 1.451  
SVWN   1.448     1.451   1.451                  
BLYP 1.519 1.476 1.476 1.479 1.479 1.478 1.479 1.474 1.473 1.474     1.479 1.472 1.479  
B1B95 1.496 1.459 1.459 1.461 1.462 1.462 1.463 1.458 1.458 1.460     1.462 1.457 1.462  
B3LYP 1.506 1.465 1.465 1.468 1.470 1.469 1.470 1.465 1.465 1.466 1.463 1.464 1.470 1.464 1.470  
B3LYPultrafine         1.470   1.470                  
B3PW91 1.499 1.461 1.461 1.464 1.465 1.465 1.465 1.461 1.460 1.462     1.464 1.460 1.465  
mPW1PW91 1.496 1.459 1.459 1.462 1.464 1.463 1.463 1.459 1.459 1.461     1.462 1.458 1.464  
M06-2X         1.469                      
PBEPBE 1.506 1.468 1.468 1.471 1.471 1.470 1.470 1.465 1.465 1.467 1.464   1.469 1.464 1.470  
PBEPBEultrafine         1.471                      
HSEh1PBE         1.463                      
Moller Plesset perturbation MP2FC 1.516 1.478 1.478 1.484 1.469 1.468 1.469 1.468 1.468 1.463   1.463 1.475 1.463 1.476  
MP2FU 1.515 1.478 1.478 1.484 1.467 1.466 1.467 1.466 1.466 1.457     1.473 1.456    
MP3         1.473                      
MP4   1.484     1.475                      
B2PLYP         1.470   1.470                  
Configuration interaction CID   1.471 1.471 1.476 1.468     1.467 1.467              
CISD   1.472 1.472 1.477 1.468     1.467 1.467              
Quadratic configuration interaction QCISD 1.522 1.483 1.483 1.488 1.476 1.475 1.476 1.475 1.476 1.471            
QCISD(T)         1.477                      
Coupled Cluster CCD 1.521 1.481 1.481 1.487 1.474 1.474 1.474 1.473 1.474 1.469            
CCSD(T)         1.477                      

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 1.487 1.489 1.479 1.482 1.471 1.471
density functional B1B95 1.487 1.484        
B3LYP 1.495 1.491 1.486 1.483 1.476 1.476
Moller Plesset perturbation MP2FC 1.514 1.491 1.503 1.482 1.497 1.497
Values that are outliers may reflect different atom numbering for different levels of theory.
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