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

Geometry Comparison

NCl (nitrogen monochloride)


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

Experimental bond length is 1.611  Å

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Calculated bond length in Å
Methods with predefined basis sets
semi-empirical AM1 1.558
PM3 1.510
PM6 1.569
composite G2 1.604
G3 1.604
G3B3 1.620
G4 1.600
CBS-Q 1.604

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(D+d)Z cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ
hartree fock HF 1.752 1.782 1.660 1.753 1.604 1.604 1.602 1.607 1.607 1.585 1.612 1.614 1.586 1.577 1.607 1.584 1.576 1.658 1.639 1.671 1.639
ROHF 1.773 1.826 1.726 1.800 1.664 1.664 1.663 1.668 1.668 1.654   1.677 1.656 1.649 1.673 1.655 1.649 1.658 1.639   1.639
density functional LSDA 1.766 1.641 1.641 1.739 1.598 1.598 1.594 1.597 1.597 1.574   1.605 1.574 1.593 1.596 1.570 1.591 1.614 1.590 1.630 1.592
SVWN   1.758     1.627   1.594                            
BLYP 1.803 1.808 1.697 1.788 1.645 1.645 1.641 1.649 1.649 1.621   1.653 1.622         1.665 1.642 1.681 1.643
B1B95 1.765 1.651 1.651 1.744 1.602 1.602 1.598 1.604 1.604 1.581   1.610 1.582 1.572 1.601 1.578 1.571 1.626 1.607 1.640 1.607
B3LYP 1.779 1.783 1.671 1.761 1.620 1.620 1.616 1.623 1.623 1.597 1.622 1.628 1.598 1.587 1.618 1.593 1.585   1.623 1.661 1.623
B3LYPultrafine         1.621                     1.598          
B3PW91 1.770 1.769 1.655 1.748 1.607 1.607 1.603 1.608 1.608 1.585   1.614 1.585         1.632   1.648 1.612
mPW1PW91 1.765 1.764 1.649 1.742 1.602 1.602 1.598 1.604 1.604 1.580   1.609 1.581           1.609 1.644 1.609
M06-2X         1.598                         1.638 1.616 1.652 1.617
PBEPBE 1.785 1.786 1.672 1.766 1.623 1.623 1.619 1.625 1.625 1.600   1.630 1.601 1.591 1.620 1.597 1.589 1.642 1.621 1.658 1.622
PBE1PBE         1.600                                
HSEh1PBE         1.638                         1.628 1.608 1.643 1.609
TPSSh         1.647   1.645           1.635                
Moller Plesset perturbation MP2 1.764 1.790 1.663 1.766 1.593 1.593 1.588 1.591 1.591 1.571 1.595 1.606 1.571 1.558 1.600 1.566   1.640 1.612 1.653 1.626
MP2=FULL 1.763 1.790 1.663 1.766 1.591 1.591 1.586 1.590 1.590 1.566   1.604 1.567 1.554 1.598 1.561   1.638 1.606 1.652  
ROMP2 1.790 1.844 1.721 1.819 1.641 1.641 1.637 1.639 1.639 1.620   1.655 1.619 1.605 1.652 1.615 1.604 1.638 1.609   1.609
MP3         1.604   1.635                     1.654 1.626   1.626
MP3=FULL         1.634   1.632                            
MP4   1.815     1.617       1.615       1.636         1.656 1.626 1.669 1.626
B2PLYP         1.614               1.631                
Configuration interaction CID   1.804 1.671 1.778 1.604     1.601                          
CISD   1.810 1.675 1.786 1.607     1.605                          
Quadratic configuration interaction QCISD   1.843 1.696 1.831 1.625 1.625 1.622 1.624 1.624 1.601   1.639 1.601         1.659 1.628 1.673 1.627
QCISD(T)         1.630             1.644 1.608   1.640 1.604   1.663 1.632 1.677 1.631
Coupled Cluster CCD   1.817 1.682 1.789 1.611 1.611 1.606 1.609 1.609 1.588   1.625 1.588   1.618 1.584   1.655 1.626 1.669 1.625
CCSD         1.616                                
CCSD(T)                       1.640 1.603 1.589 1.635 1.600   1.661 1.630 1.675 1.629
CCSD(T)=FULL         1.660                 1.585       1.658 1.624 1.673 1.626

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 1.747 1.619 1.745 1.617 1.757 1.760
density functional B3LYP 1.770 1.641 1.765 1.637 1.768 1.766
Moller Plesset perturbation MP2 1.769 1.616 1.762 1.610 1.768 1.769
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
Please use the error report form to report problems.