First-principles investigation of A₂GeBeBr₆ (A = Rb, K) halide double perovskites for advanced optoelectronic and photonic devices

Materials Today Communications 2026 Open access

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Authors: Yazen M. Alawaideh, Bashar. M. Al-Khamiseh, Samer Alawaideh, Aya M. Al-Zuheir, Waed Alahamad, Ioan-Lucian Popa, Nehad Ali Shah
DOI: 10.1016/j.mtcomm.2026.114651
Cited by: 2
References: 89

Abstract

We present a first-principles DFT study of lead-free halide double perovskites A₂GeBeBr₆ (A = Rb, K) using the TB-mBJ functional. Both compounds stabilize in a cubic Fm-3m structure with lattice parameters of 10.758 Å (Rb) and 10.632 Å (K). They exhibit indirect band gaps suitable for visible-light harvesting and show ductile mechanical behavior. The calculated optical properties, including strong UV absorption and moderate dielectric constants, suggest potential for optoelectronic applications. This work provides fundamental insights into this unexplored material class and supports the design of lead-free perovskites for renewable energy technologies.

Fields of Study & Subjects

Perovskite Materials and Applications Heusler alloys: electronic and magnetic properties Thermal Expansion and Ionic Conductivity

Publication details

Journal / source
Materials Today Communications
Publisher
Elsevier BV
Volume
50
Pages
114651–114651
Publication date
1 January 2026
Language
EN