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Computational Methods. Spartan Student Physical Chemistry Edition provides a targeted set of computational methods to address the needs of educators and students. All methods are easily accessed via Spartan's seamless graphical interface, putting real computational power at your fingertips.
   
Methods:
     
  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.
     
  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 Physical Chemistry Edition, 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.
     
  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. Three basis sets are included: 3-21G, 6-31G* and 6-311+G**.
     
  Density Functional
Theory (B3LYP)		 Density functional models typically provide results of a quality comparable to conventional correlated models such as MP2, but with a computational time only slightly greater than that of Hartree-Fock models. As such, they are particularly useful for high-quality structure, energy and property calculations, including calculations on transition-metal inorganic and organometallic compounds. B3LYP models are supported for 6-31G* and 6-311+G* basis sets and for molecules containing up to 20 atoms.
     
  Møller-Plesset (MP2) MP2 is perhaps the simplest model to take reasonable account of electron correlation, and generally provides accurate descriptions of equilibrium structure, conformation and energetics of a variety of chemical reactions, including reactions where chemical bonds are broken. MP2 is supported for 6-31G* and 6-311+G** basis sets and for molecules containing up to 20 atoms.