1
Department of Physics, Urmia University of Technology, Urmia, Iran
2
Department of Physics, Faculty of Science, University of Tabriz, Tabriz, Iran
10.24200/sci.2026.68002.10934
Abstract
The global pursuit of sustainable and non-toxic materials for optoelectronic applications has directed increasing attention toward lead-free halide perovskites. In this study, the structural, electronic, optical, and mechanical properties of Ca3PBr3 were systematically investigated using first-principles calculations based on density functional theory (DFT). Both the generalized gradient approximation (GGA-PBE) and the hybrid HSE06 exchange-correlation functional were employed, with spin–orbit coupling (SOC) incorporated to capture relativistic effects. The results reveal that Ca3PBr3 possesses a direct bandgap of 1.64 eV (GGA) and 2.47 eV (HSE06), which can be efficiently tuned within a range of 0.38 eV under biaxial strain from -4% to +4%. The projected density of states (PDOS) indicates that the valence band is primarily derived from Br-4p and P-3p orbitals, while Ca-3d states dominate the conduction band. Optical analyses show strong light absorption in the visible range, with strain-dependent modulation of the absorption edge, refractive index, and dielectric function. Mechanical stability tests confirm that Ca3PBr3 satisfies the Born criteria under all applied strain conditions, maintaining robust structural integrity. These findings identify Ca3PBr3 as a mechanically stable, environmentally benign, and strain-tunable semiconductor suitable for next-generation flexible optoelectronic, piezoelectric, and spintronic devices.
Nemati, F. , Habibpourbisafar, R. and Javanshoor, E. (2026). Strain-Tunable Electronic and Optical Properties of Lead-Free Halide Perovskite Ca3PBr3: A First-Principles Study. Scientia Iranica, (), -. doi: 10.24200/sci.2026.68002.10934
MLA
Nemati, F. , , Habibpourbisafar, R. , and Javanshoor, E. . "Strain-Tunable Electronic and Optical Properties of Lead-Free Halide Perovskite Ca3PBr3: A First-Principles Study", Scientia Iranica, , , 2026, -. doi: 10.24200/sci.2026.68002.10934
HARVARD
Nemati, F., Habibpourbisafar, R., Javanshoor, E. (2026). 'Strain-Tunable Electronic and Optical Properties of Lead-Free Halide Perovskite Ca3PBr3: A First-Principles Study', Scientia Iranica, (), pp. -. doi: 10.24200/sci.2026.68002.10934
CHICAGO
F. Nemati , R. Habibpourbisafar and E. Javanshoor, "Strain-Tunable Electronic and Optical Properties of Lead-Free Halide Perovskite Ca3PBr3: A First-Principles Study," Scientia Iranica, (2026): -, doi: 10.24200/sci.2026.68002.10934
VANCOUVER
Nemati, F., Habibpourbisafar, R., Javanshoor, E. Strain-Tunable Electronic and Optical Properties of Lead-Free Halide Perovskite Ca3PBr3: A First-Principles Study. Scientia Iranica, 2026; (): -. doi: 10.24200/sci.2026.68002.10934
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