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602. OVGF(SEMI):Molecular Orbital Package for Outer
Valence Green's Function Calculations Coupled with the
MNDO, MNDOC, AM1, PM3 Semiempirical Approximations
by David Danovich, Margaret Thatcher Centre for Computational Chemistry, Department of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel The present program has been designed for calculating ionization potentials of organic molecules by using the Green's function formalism1, coupled with the semiempirical approximations MNDO2, MNDOC3, AM14 and PM35. The SCF part of the MNDOC (QCPE 438) program was rewritten.To analyze the electronic structure reorganization, the outer-valence Green's function (OVGF) technique1 was used with the self-energy part extended up to the third-order perturbation theory corrections. The higher order contributions were estimated by using the renormalization procedure6. The expressions for the numerical calculations were taken from Ref. 6. Semiempirical SCF calculations are carried out according to the MNDO, MNDOC, AM1 or PM3 approximations. Closed-shell system are treated by the standard Roothan method7. In the OVGF calculations all MOs are included in the active space. Molecular geometries are optimized by the Davidon- Fletcher-Powell (DFP) algorithm. There are options for imposing symmetry restrictions and for keeping specified variables constant during the optimization. In the semiempirical programs parameters are available for the following atoms: MNDO H Be B C N O F Al Si P S Cl Ge Br Sn I AM1 H C N O F Al Si P S Cl Br I PM3 H C N O F Al Si P S Cl Br I For a brief description of the program and results see References 9, 10. _________ References: 1. L. S. Cederbaum, J. Phys. Ser. B., 8, 290 (1975). 2. M.J.S Dewar and W. Thiel, J. Am. Chem. Soc., 99, 4899 (1977). 3. W. Thiel, J. Am. Chem. Soc., 103, 1413 (1989). 4. M.J.S. Dewar, E. G. Zoebisch, E. F. Healy and J.J.P. Stewart, J. Am. Chem. Soc., 107, 3902 (1985). 5. J.J.P. Stewart, J. Comp. Chem., 10, 209, 221 (1989) 6. W. von Niessen, J. Schirmer and L. S. Cederbaum, Comp. Phys. Rep., 1, 57 (1984). 7. C.C.J. Roothan, Rev. Mod. Phys., 23, 69 (1951). 8. R. Fletcher and M.J.D. Powell, Comp. J., 6, 163 (1963) and W. C. Davidon, Comp. J., 10, 406 (1968). 9. D. Danovich, V. Zakzewskii and E. S. Domnina, J. Mol. Struct. (Theochem), 187, 297 (1989). 10. D. Danovich, V. Zakzewskii and E. S. Domnina, J. Mol. Struct. (Theochem), 188, 159 (1989). _________ NOTE:Due to the file structure of this program, it is being delivered in VAX COPY (ANSI D) format only. One should also keep in mind that this system contains very large DIMENSIONS, and during testing it was found necessary to increase a system variable from the standard 10,000 virtual pages to about 64,000 pages in order to compile and link the system. The virtual page count can not be increased by a user; it must be done by a systems programmer. Lines of Code: 8654 VAX/VMS FORTRAN-77 |