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Methods: |
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Molecular Mechanics |
Molecular mechanics is presently the only practical method for calculations
on very large molecules. Molecular mechanics models may be applied
to molecules containing up to 1,000 atoms. MMFF94 has been specifically
parameterized to reproduce geometries and conformations of organic
molecules and biopolymers. |
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Semi-Empirical
Molecular Orbital |
Semi-empirical models are the simplest of the quantum chemical schemes,
and are useful for equilibrium and transition-state structure calculations.
The semi-empirical method included in the Student Version, PM3, has
proven to be a reliable tool for geometry calculations on transition
metal inorganic and organometallic compounds. Semi-empirical models
are applicable to molecules containing up to 50 atoms. PM3 parameters
for most transition metals are now available. |
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Hartree-Fock
Molecular Orbital |
Hartree-Fock models are ideal for structure, energy and property
calculations, in particular for organic molecules. They are applicable
to molecules containing up to 30 atoms. Two extensive basis sets are
included: 3-21G and 6-31G*. |
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