Systematic trends in boron icosahedral structured materials

Boron materials exist in many different structures with an important similarity that they all contain connected B12 icosahedra. Various structures that hold potential for super-hard material properties are examined using ab initio computational techniques. Systematic trends are established. The charge density between all B–B bonds in each structure that are examined and it is suggested that hardness of the material may, in part, relate to the average charge density between the boron bonds. Atoms connecting the B icosahedra donating charge that enhance the strength of the B–B bonds.