Ab initio bond orders/valencies

[peeter[ AT ]chem.ut.ee (Peeter Burk)]

 Dear netters,
 In order to estimate the aromaticity of some little cyclic
 compounds I would like to calculate the bond orders and bond
 valences at ab initio level using methods proposed by K.Jug (K.Jug,
 J.Am.Chem.Soc., 99, 7800 , 1977; M.S.Gopinathan and K.Jug,
 Theor.Chim.Acta, 63, 497, 511, 1983).
 As much as I understand, the calculation of above mentioned
 parameters from ab initio calculation results is quite
 straightforward, if you have the density matrix, corresponding to
 orthonormal set of atomic orbitals.
 The problem is, that the density matrix you can get from routine ab
 initio calculations (Gaussian, etc.) to my best knowledge does not
 correspond to orthonormal atomic orbitals.
 So my question is how can I get from my Gaussian92 calculation
 results the density matrix corresponding to orthonormal atomic
 orbitals? Is there any program, which can do the trick? Or even
 better, calculate for me directly the bond orders and valencies?
 Thanking you in advance,
                        Peeter Burk
 --
 Peeter Burk                             Jakobi 2, EE2400 Tartu, Estonia
 Institute of Chemical Physics           Phone (372-34) 31-263
 Tartu University                        Fax   (372-72) 41-453
 Estonia                                 E-mail peeter[ AT ]chem.ut.ee