A new program for radical tessellation construction and analysis

The purpose of this work is to describe usage of computer program SIMPL designed for construction and analysis of radical tessellations of any computer simulated sample. The radical polyhedra (RP) [Gellatly B J and Finney J L 1982 J. Non-Cryst. Solids 50 313] can be considered as a generalization of the Voronoi polyhedra more widely used in literature. RP is a minimal polyhedron whose faces are sets of such points that distances from the points to tangent points of two neighboring atomic spheres are equal. The tessellation technique is a very efective tool for structural analysis of computer simulated samples, giving a great amount of easily accessible information. SIMPL allows to construct RP network for defined system and analyze shape, composition and mutual geometrical relation of radical polyhedra and radical simplices. Implemented capabilities give, for example, the posibility to recognize atomic environments’ shape and investigate the non-local order in computer simulated materials. The pattern recognition technique [Laskowski R et al. 1997 TASK Quart. 1 96] is based on analysis of the shape of the radical polyhedra, and contraction of short edges and small faces of the polyhedra. Non-local order analysis involves geometric relations between tessellation simplices.