Atomic radius

Measure of the size of an atom

The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Five widely used definitions of atomic radius are covalent radius, Van der Waals radius, charge radius, ionic radius, and metallic radius.

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