Overlapping electron density and the global delocalization of <i>π</i>‐aromatic fragments as the reason of conductivity of the biphenylene network

Abstract

Abstract Recently fabricated 2D biphenylene network is an astonishing solid‐state material, which possesses unique metal‐like conductive properties. At the same time, two‐dimensional boron nitride network (2D‐BN)—an isoelectronic and structural analogue of biphenylene network, is an insulator with a wide direct bandgap. This study investigates the relationship between the electronic properties and chemical bonding patterns for these species. It is shown that the insulating 2D‐BN network possesses a strong localization of electron density on the nitrogen atoms. In turn, for a carbon‐containing sheet, we found a highly delocalized electron density and an appreciable overlap of p z orbitals of neighboring C 6 rings, which might be a reason for the conductive properties of the material.