Particle Packing in a Crystal

Abstract

The branch of science which deals with regularities in the arrangement of particles (atoms, ions, and molecules) in a crystal is called crystal chemistry. This term is obviously a misnomer; it seems more appropriate for a science dealing with chemical transformations in the crystalline state. But, strange as it may seem, scientists working in solid-state chemistry do not call themselves crystal chemists. As a matter of fact, crystal chemistry can be considered as a part of solid-state physics. But its descriptive character and the necessity of dealing with structural data on thousands of compounds are the obvious reasons why solid-state physicists refuse to have anything to do with the packing of particles. They believe the methods used in crystal chemistry to be closer to chemistry than to physics.