Molecular Modeling

 Molecular modeling  may be a collection of techniques for deriving, representing and manipulating the structures and reactions of molecules, and people properties that are hooked in to these three dimensional structures. Molecular modelling encompasses all methods, theoretical and computational, wont to model or mimic the behaviour of molecules. The methods are utilized in the fields of computational chemistry, computational biology and materials science to review molecular systems starting from small chemical systems to large biological molecules and material assemblies. The simplest calculations are often performed by hand, but inevitably computers are required to perform molecular modelling of any reasonably sized system. The common feature of molecular modelling methods is that the atomistic level description of the molecular systems. This may include treating atoms because the smallest individual unit or explicitly modelling protons and neutrons with its quarks, anti-quarks and gluons and electrons with its photons. Molecular mechanics is one aspect of molecular modelling, because it involves the utilization of Newtonian mechanics to explain the physical basis behind the models. Molecular models typically describe atoms as point charges with an associated mass. The interactions between neighbouring atoms are described by spring-like interactions and Van der Waals forces. The Lennard-Jones potential is usually wont to describe the latter. The electrostatic interactions are computed based on Coulomb's law. Atoms are assigned coordinates in Cartesian space or in internal coordinates, and may even be assigned velocities in dynamical simulations. The atomic velocities are associated with the temperature of the system, a macroscopic quantity.