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

Geometry Comparison

C5H8 (Cyclopentene)


distance is atom 2 (C) to atom 4 (C)

Experimental bond length is 1.518  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 1.495
PM6 1.515
composite G2 1.511
G3 2.351
G3B3 1.513
CBS-Q 2.354

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 1.523 1.522 1.522 1.512 1.511 1.511 1.511 1.511 1.511 1.510 1.509 1.509 1.511 1.508 1.512 1.508
density functional LSDA 1.518 1.508 1.508 1.501 1.495 1.495 1.496 1.493 1.493 1.493     1.496 1.490 1.495  
SVWN   1.509     1.495   1.498                  
BLYP 1.547 1.535 1.535 1.528 1.522 1.522 1.524 1.521 1.521 1.520     1.523 1.517 1.522  
B1B95 1.524 1.518 1.518 1.509 1.503 1.503 1.504 1.502 1.502 1.502     1.503 1.499 1.502  
B3LYP 1.536 1.524 1.524 1.517 1.513 1.513 2.366 1.512   1.511 1.509 1.512 1.513 1.508    
B3LYPultrafine         1.513   1.514                  
B3PW91   1.521 1.521 1.513 1.508 1.507 1.508 1.506   1.506     1.507 2.351 1.508  
mPW1PW91   1.518 1.518 1.510 1.506 1.505 1.506 1.504 1.504 1.504     1.505 1.501 1.506  
M06-2X         1.511                      
PBEPBE   1.527     1.513 1.513 1.514 1.511 1.512 1.512 1.509   1.513 1.509    
PBEPBEultrafine         1.513                      
HSEh1PBE         1.507                      
Moller Plesset perturbation MP2FC   1.534 1.534 1.528 1.509 1.508 1.509 1.512 1.512 1.508   1.507 1.516 1.506    
MP2FU   1.534 1.534 1.528 1.507 1.506 1.508 1.510         1.514 1.500    
MP3         1.513                      
MP4       1.528                        
B2PLYP         1.512   1.513                  
Configuration interaction CID         2.350                      
CISD         2.351                      
Quadratic configuration interaction QCISD   1.540 1.540 1.533 1.514 1.513 1.515 1.517 1.518       1.522      
Coupled Cluster CCD   1.538 1.538 1.532 1.513 1.512 1.514 1.516         1.521      

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 1.529 1.525 1.525 1.520 1.519 1.518
density functional B1B95 1.529 1.522        
B3LYP 1.538 1.530 1.531 1.525 1.523 1.523
Moller Plesset perturbation MP2FC 1.555 1.529 1.545 1.521 1.542 1.542
Values that are outliers may reflect different atom numbering for different levels of theory.
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