Electron Energy Structure of Boron Nitride and Diamond. Similarities and Distinctions

With the coherent potential method of the multiple scattering theory the electronic structure of boron nitride (in sphalerite modification) and diamond is calculated. The cluster approximation with muffin‐tin crystal potential is used. The electron structure and chemical bonding of these substances are investigated for the first time with this modern theoretical method. It is shown that the chemical bonding has mainly covalent character, the ionicity being about 20%. A fine structure of the upper part of the valence band of boron nitride is revealed and its nature is discussed. The similarity of the total electron state densities of the diamond and boron nitride in sphalerite modification is proved and the distinctions are discussed. The calculated local partial electron densities of states are used to explain the experimental X‐ray emission and X‐ray photoemission spectra of diamond and boron nitride.