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Geometry of a simplified molecule in two-dimensional space for illustration. (a) The molecule formed by the union of atom disks. Voronoi diagram is in dashed lines. (b) The shape enclosed by the boundary polygon is tessellated by the Delaunay triangulation. (c) The alpha shape of the molecule is formed by removing those Delaunay edges and triangles whose corresponding Voronoi edges and Voronoi vertices do not intersect with the body of the molecule. A molecular void can be seen, and is represented in the alpha shape by two empty triangles (Adapted from [5]).  

Geometry of a simplified molecule in two-dimensional space for illustration. (a) The molecule formed by the union of atom disks. Voronoi diagram is in dashed lines. (b) The shape enclosed by the boundary polygon is tessellated by the Delaunay triangulation. (c) The alpha shape of the molecule is formed by removing those Delaunay edges and triangles whose corresponding Voronoi edges and Voronoi vertices do not intersect with the body of the molecule. A molecular void can be seen, and is represented in the alpha shape by two empty triangles (Adapted from [5]).  

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