Calculation of system's properties by means of a numerical evaluation of an algorithm embodying relevant physical laws. Numerical modeling has become an important tool in modern science, and nanoscience is no exception (the so-called computational nanotechnology). Most important methods in this context are molecular dynamics calculations (or classical monte carlo calculations) and density functional calculations. Molecular dynamics methods study evolution and properties a system consisting of classical particles. They do not account for quantum nature of the system and this is their main limitation. A very simple and inaccurate example of molecular dynamics calculations is used in a movie representing deposition of atoms on surface (interference nanolithography, see below). There are also quantum monte carlo calculations (diffusion monte carlo, feynman path integrals monte carlo...), but these are still limited to systems consisting of small number of particles. As the computer power grows, quantum monte carlo calculations are expected to dominate the field of nanoscience. Density functional methods enable one to evaluate the (ground state) electronic properties of the system. Numerical approaches to visualization of a system, its properties and its dynamics are also an example of a (perhaps somewhat primitive) numerical modeling.

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