Related Experiment Video
Updated: Mar 29, 2026

Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
The effect of vacancies on the optical properties of AuAl₂
V J Keast1, J W Wallace, C J Wrightson
1School of Mathematical and Physical Sciences, University of Newcastle, Callaghan NSW 2308, Australia.
Abstract:
AuAl2 is an intermetallic compound with a vivid purple colour attributable to a bulk plasmon energy in the visible part of the spectrum. However, the colour of as-deposited thin films is not as strong and only develops upon annealing. Density functional theory calculations of the dielectric function are presented for a variety of vacancy types and concentrations. The results support the view that the effect of annealing on colour is correlated with a reduction in concentration of Al vacancies. The effect of vacancies on the optical properties can be understood as arising from the complex interplay between interband transitions around the Fermi level and the plasmon energy.
Related Concept Videos
Imperfections in Crystal Structure: Stoichiometric Point Defects
Imperfections in Crystal Structure: Non-Stoichiometric Defects
Properties of Enantiomers and Optical Activity
UV–Vis Spectroscopy: Molecular Electronic Transitions
IR and UV–Vis Spectroscopy of Aldehydes and Ketones
π Molecular Orbitals of the Allyl Cation and Anion

