Crystal orbital scheme for Si3N4

The crystal orbital (CO) scheme is constructed for beta-Si3N4 to display the bonding in the solid compound. The electronic band structure is obtained within the extended Huckel tight-binding approach for periodical systems. For the purpose of comparison features of the electronic structure are contrasted for a series of SiC, Si3N4. and SiO2. Partial DOS are displayed to highlight orbital interactions. Combined with bonding properties of states they are used to assign simplified interaction diagram consisting of atomic energy levels, total DOS distribution and interaction lines. The interaction scheme provides well-arranged synoptical picture showing fundamental factors responsible for the final distribution of energy states. Via the CO scheme the bonding in beta-Si3N4 is displayed in the form understandable to people with no knowledge of quantum mechanics. (C) 1998 Elsevier Science Limited and Techna S.r.l. All rights reserved.