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

Geometry Comparison

AlH (aluminum monohydride)


distance is atom 1 (Al) to atom 2 (H)

Experimental bond length is 1.648  Å

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Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.662
PM6 1.608
composite G2 1.652
G3 1.652
G3B3 1.673
G4 1.661
CBS-Q 1.652

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 aug-cc-pVQZ cc-pV(D+d)Z cc-pV(T+d)Z
hartree fock HF   1.677 1.650 1.687 1.652 1.651 1.651 1.646 1.648 1.646 1.648 1.652 1.660 1.652 1.648 1.659 1.652 1.648 1.651 1.648
density functional LSDA 1.600 1.716 1.686 1.724 1.689 1.687 1.687 1.681 1.682 1.678     1.696 1.680   1.692     1.687 1.675
SVWN   1.716     1.689   1.687                          
BLYP   1.712 1.683 1.722 1.688 1.685 1.686 1.680 1.681 1.676     1.693 1.679   1.690     1.685 1.674
B1B95 1.590 1.697 1.670 1.706 1.671 1.671 1.671 1.666 1.667 1.663     1.678 1.666   1.675     1.669 1.661
B3LYP 1.595 1.698 1.669 1.707 1.673 1.671 1.671 1.665   1.662 1.662 1.669 1.679 1.666 1.660 1.676 1.665 1.660 1.670 1.661
B3LYPultrafine         1.673                       1.663      
B3PW91   1.701 1.672 1.709 1.674 1.673 1.673 1.668   1.665     1.680 1.668   1.678     1.672 1.664
mPW1PW91 1.583 1.698   1.707 1.671 1.670 1.669 1.664 1.665 1.662     1.677 1.666   1.676     1.669 1.661
M06-2X         1.662                           1.659 1.649
PBEPBE   1.717     1.691 1.689 1.689 1.684 1.685 1.681 1.680   1.698 1.684     1.683   1.689 1.679
PBEPBEultrafine         1.691                              
PBE1PBE         1.674                              
HSEh1PBE         1.675                           1.672 1.664
TPSSh         1.664   1.663             1.660            
Moller Plesset perturbation MP2   1.695 1.656 1.706 1.659 1.647 1.646 1.650 1.645 1.641   1.649 1.658 1.651 1.647 1.664 1.652 1.648 1.650 1.646
MP2=FULL   1.695     1.659 1.646 1.646 1.651         1.658   1.616 1.660     1.649 1.644
MP3         1.664   1.648                       1.650 1.649
MP3=FULL         1.663   1.647                          
MP4   1.710     1.668     1.660           1.656         1.651 1.651
B2PLYP         1.665                 1.657            
Configuration interaction CID         1.667     1.659           1.654            
CISD   1.712     1.669                 1.655            
Quadratic configuration interaction QCISD   1.715 1.726   1.671 1.651 1.650 1.662 1.648       1.661 1.655         1.651 1.651
QCISD(T)         1.672 1.652 1.651 1.663         1.662 1.657            
Coupled Cluster CCD   1.711     1.668 1.649 1.649 1.660         1.659 1.654         1.650 1.650
CCSD         1.670 1.651 1.650 1.662         1.661 1.655            
CCSD(T)   1.715     1.672 1.652 1.651 1.663 1.648       1.662 1.657         1.653 1.652
CCSD(T)=FULL                                     1.652 1.650

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 1.695 1.664 1.686 1.666 1.677 1.656
density functional B1B95 1.714 1.683        
B3LYP 1.713 1.681 1.711 1.685 1.697 1.677
Moller Plesset perturbation MP2 1.717 1.674 1.709 1.674 1.699 1.671
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
Please use the error report form to report problems.