Magnetic contribution to the atomic volume of d group transition metals

A simple relation is presented to describe the dependence of the volume of a d group metal atom on its magnetic moment using a single constant independent of the atom involved, the crystal structure, atomic enviroment, type and strength of magnetic order. This relation is extended to binary alloys and its significance in special cases discussed. The validity of this relation is checked for a wide range of Fe, Mn and Cr binary alloy systems in subsequent papers.