3d transition metal impurities in diamond: electronic properties and chemical trends

TL;DR

This study uses first principles calculations to analyze how 3d transition metal impurities from Sc to Cu affect the electronic properties of diamond, revealing trends in energy levels and site preferences.

Contribution

It provides a detailed analysis of the electronic properties and chemical trends of 3d transition metal impurities in diamond using first principles calculations, highlighting site-dependent behaviors.

Findings

Impurities have low formation energies in substitutional and semi-vacancy sites.

Energy levels shift from the top of the bandgap toward the valence band across the series.

Weak interaction between divacancy and 3d orbitals in the double semi-vacancy site.

Abstract

First principles calculations have been used to investigate the trends on the properties of isolated 3d transition metal impurities (from Sc to Cu) in diamond. Those impurities have small formation energies in the substitutional or double semi-vacancy sites, and large energies in the interstitial one. Going from Sc to Cu, the 3d-related energy levels in the bandgap move from the top of the bandgap toward the valence band in all three sites. Trends in electronic properties and transition energies of the impurities, in the substitutional or interstitial sites, are well described by a simple microscopic model considering the electronic occupation of the 3d-related levels. On the other hand, for the impurities in the double semi-vacancy site, there is a weak interaction between the divacancy- and the 3d-related orbitals, resulting in in vacancy- and 3d-related levels in the materials bandgap.