Theories of bonding in metals

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The honding and structures adopted hy metals and alloys arc less fully understood than those with ionic and covalent compounds. Any successful theory of metallic bonding must explain both the bonding between a large number of identical atoriJs· in a pure, metal, and the bonding between widely different metal atoms in alloys. The the.ory cahnot involve directional bonds, since most metallic properties remain even when the metal is in the liquid state (for example mercury), or when dissolved in a suitable solvent (for example solutions of sodium in liquid ammonia). Further, the theory should explain the great mobility of electrons.

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