--------------------------------------------------------------------
                SEMINAR OF THE DYNAMICAL SYSTEMS GROUP
        Institute for Computational Sciences and Informatics
--------------------------------------------------------------------

         		Molecular Mechanics

                        Suzanne W. Slayden
          Chemistry Department, George Mason University

	Over the last 25 years or so, molecular mechanics has 
developed into a standard powerful method for studying molecular 
structure and related properties.  The major distinction between the 
molecular mechanical and quantum mechanical approaches to 
studying molecular structure is that molecular mechanics does not 
usually consider the electrons in the molecule explicitly.  
Molecular mechanics treats the atoms and their associated 
electrons as units interconnected by potential functions whose 
mathematical form is familiar from classical mechanics.  The 
resulting force field contains adjustable parameters that are 
optimized to obtain the best fit of calculated and experimental 
properties of the molecules, such as geometries, conformational 
energies, heats of formation, or other properties.  All of the 
equations are sufficiently simple that they can be solved very 
rapidly with modern computers and thus permit calculations on 
even very large molecules.  Molecular mechanics calculations will 
be demonstrated using HyperChem molecular modeling software.  

		      Monday , April 17, 1995
			        5:30 pm
		      Room 310, Science & Tech. I
-------------------------------------------------------------------