Connections between local and macroscopic properties in solids: The case of N in III-V-N alloys

Although it is well known that dilute species often significantly modify the properties of solids in which they are hosted, a basic question remains open: How critical are their local properties in determining the macroscopic ones of the host material? Here we address this issue by taking N in dilute III-V-N alloys as a paradigmatic case and propose an original approach based on synergic progress in x-ray spectroscopies, density functional theory simulations, and hydrogen exposure as a tool to modify local bonding. In this way we are able to clarify how local properties operate by identifying the coupling mechanism between specific atomic orbitals responsible for the changes of both deep and band edge states. The success of our approach indicates a new way to connect local and macroscopic properties.