Metallic Solids

A metallic solid can be pictured as an orderly collection of positive metal ions immersed in a "sea" of free electrons. Each metal atom contributes one or more electrons to this common pool, and these electrons are mobile and spread evenly throughout the crystal.

This sea of delocalised electrons explains the characteristic properties of metals:

• High electrical conductivity — when an electric field is applied, the free electrons drift through the network of positive ions.
• High thermal conductivity — heat supplied at one point is carried rapidly throughout by the mobile electrons. …