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The CAChe ZINDO package is a semi-empirical, quantum mechanical calculation. This program uses Prof. Zerner's Intermediate Neglect of Differential Overlap. This technique includes methods to optimize the geometry of your molecule as well as methods to give information concerning the location of electron density within your system. CAChe ZINDO has full parameterization for H, B, C, N, O, F, Li, P, S, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn. These elements have theoretical and spectroscopic INDO/1 parameters. Elements which have only theoretical INDO/1 parameters are Be, Na, Mg, Al, Si, Cl, K, Ca, As, Br, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd and I. The Self Consistent Field method is used to iteratively determine the molecular orbitals for your system until energy is minimized. Restricted Hartree-Fock is the CAChe default and is best used for closed shell systems. Unrestricted Hartree-Fock can be implemented for open shell systems. ZINDO calculations give you information concerning the optimized geometry of your molecule, the frontier molecular orbitals, electron density distribution, partial charges, dipole moment, bond order, ionization potentials, electron affinities, electronic spectra and effects of solvation for your molecule. These results can be displayed with your molecule in the chemical sample window. This program is slower than the Extended Huckel calculations; however, ZINDO calculations allow you to minimize the geometry of your system as well as obtain information concerning the location of valence electrons in your system.
CAChe references:
Ridley, J., Zerner, M. C., Theoret. Chim. Acta
1976, 42, 223.
Pople, J. A., Beveridge, D. L. Dobosh, P. A., J. Chem. Phys. 1967,
47, 2026.
Detailed information on Molecular Modeling is available at the NIH Molecular Modeling Home Page
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