The Wigner--Seitz cell of a lattice point consists of points at least as close to it as to every other lattice point. Its faces lie on perpendicular bisectors to neighbouring lattice points.
The Wigner-Seitz cell is a concept in solid-state physics and crystallography that is used to describe the local environment of atoms in a crystalline lattice. It is essentially a way to define a unit cell that encompasses the region around a lattice point, giving a clear representation of how space is partitioned among the particles in a crystal.
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