Newly synthesized Ti5Al2C3: Electronic and optical properties by first-principles method

TL;DR

This study uses first-principles calculations to explore the electronic and optical properties of the newly synthesized Ti5Al2C3 MAX phase, revealing its potential as a dielectric and coating material.

Contribution

It provides the first theoretical analysis of Ti5Al2C3's electronic structure and optical properties using first-principles methods.

Findings

Ti 3d electrons dominate the DOS at the Fermi level

Ti5Al2C3 has a high static dielectric constant of 130

High reflectivity up to 9.7 eV suggests coating applications

Abstract

A theoretical study of the newly identified Ti5Al2C3 belonging to the MAX phases has been performed by using the first-principles pseudopotential plane-wave method within the generalized gradient approximation (GGA). The energy band structure and optical properties are reported for the first time. It is seen that Ti 3d electrons mainly contribute to the DOS at the Fermi level, and should be involved in the conduction properties. The parameters of optical properties (dielectric function, absorption spectrum, conductivity, energy-loss spectrum and reflectivity) for Ti5Al2C3 are calculated and discussed. The material has a large positive static dielectric constant of 130 which indicates it to be a good dielectric material. Further the reflectivity of Ti5Al2C3 is high in the infrared-visible-UV region up to ~ 9.7 eV showing promise as a good coating material to avoid solar heating. Keywords: A: Ti5Al2C3; B: First-principles; C: Electronic structure; C: Optical properties