# Transition metal ions in ZnO: effects of intrashell Coulomb repulsion on electronic properties

## TL;DR

This study uses first principles calculations to explore how intrashell Coulomb repulsion influences the electronic structure and charge states of transition metal dopants in ZnO, revealing charge state dependence and spin splitting effects.

## Contribution

It provides a detailed analysis of Coulomb coupling effects on TM dopants in ZnO, highlighting the impact on charge states and spin properties, which was not thoroughly understood before.

## Key findings

- Charge state dependence of TM gap levels affects metastability.
- Exchange coupling varies across the 3d series.
- Spin splitting energy depends on chemical identity.

## Abstract

Electronic structure of the transition metal (TM) dopants in ZnO is calculated by first principles approach. Analysis of the results is focused on the properties determined by the intrashell Coulomb coupling. The role of both direct and exchange interaction channel is analyzed. The coupling is manifested in the strong charge state dependence of the TM gap levels, which leads to the metastability of photoexcited Mn, and determines the accessible equilibrium charge states of TM ions. The varying magnitude of the exchange coupling is reflected in the dependence of the spin splitting energy on the chemical identity across the 3$d$ series, as well as the charge state dependence of spin-up spin-down exchange splitting.