The relation between atomic shape and crystal structure illustrated by metallic elements

A new look at the relation between the shape of the atoms and the crystal structure of the elements is made. As a result it was possible to describe the variety of crystal structures (Cu‐, W‐, Mg‐type of structure) of pure metallic elements using a consistent principle. The guiding rule of the principle is the dense arrangement of atoms in the form of a hexagon with a central atom. Different atomic shapes and stacking arrangements lead to different unit cells. The shape of an atom is a more useful visualisation construct than the complicated charge density distribution. The consequences of the proposed model on various aspects of crystallography are discussed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)