Author:
Halati Mohamed Salah,Khyzhun Oleg Yu,Khireddine Abderrazak,Piasecki Michal,Radkowska Ilona,Cherif Khaled Hamdi,Lounis Zakia,Caudano Yves,Bedjaoui Abdelhak,Alghamdi Ahmed,Paramasivam Prabhu,Prakash Chander,Ghoneim Sherif S. M.
Abstract
AbstractIn the present work, we report on theoretical studies of thermodynamic properties, structural and dynamic stabilities, dependence of unit-cell parameters and elastic constants upon hydrostatic pressure, charge carrier effective masses, electronic and optical properties, contributions of interband transitions in the Brillouin zone of the novel Tl2HgGeSe4 crystal. The theoretical calculations within the framework of the density-functional perturbation theory (DFPT) are carried out employing different approaches to gain the best correspondence to the experimental data. The present theoretical data indicate the dynamical stability of the title crystal and they reveal that, under hydrostatic pressure, it is much more compressible along the a-axis than along the c-axis. Strikingly, the charge effective mass values ($$m_{e}^{{^{*} }}$$
m
e
∗
and $$m_{h}^{{^{*} }}$$
m
h
∗
) vary considerably when the high symmetry direction changes indicating a relative anisotropy of the charge-carrier’s mobility. Furthermore, the Young modulus and compressibility are characterized by the maximum and minimum values ($$E^{max}$$
E
max
and $$E^{\min }$$
E
min
) and ($$\beta^{max}$$
β
max
and $$\beta^{\min }$$
β
min
) that are equal to (62.032 and 28.812) GPa and (13.672 and 6.7175) TPa–1, respectively. Additionally, we have performed calculations of the Raman spectra (RS) and reached a good correspondence with the experimental RS spectra of the Tl2HgGeSe4 crystal. The XPES associated to RS constitutes powerful techniques to explore the oxidized states of Se and Ge in Tl2HgGeSe4 system.
Publisher
Springer Science and Business Media LLC
Reference68 articles.
1. Vu, T. V. et al. Insights from experiment and theory on peculiarities of the electronic structure and optical properties of the Tl2HgGeSe4 crystal. Inorg. Mater. 62, 16691–16709 (2023).
2. Li, W. et al. Cu2HgSnSe4 nanoparticles: Synthesis and thermoelectric properties. CrystEngComm 15, 8966–8971 (2013).
3. Khyzhun, O. Y., Bekenev, V. L., Ocheretova, V. A., Fedorchuk, A. O. & Parasyuk, O. V. Electronic structure of Cu2ZnGeSe4 single crystal: Ab initio FP-LAPW calculations and X-ray spectroscopy measurements. Physica B 461, 75–84 (2015).
4. Kauk-Kuusik, M. Study of Cu2CdGeSe4 monograin powders synthesized by molten salt method for photovoltaic applications. Thin Solid Films 666, 15–19 (2019).
5. Vu, T. V. et al. A theoretical and experimental study of the valence-band electronic structure and optical constants of quaternary copper mercury tin sulfide, Cu2HgSnS4, a potential material for optoelectronics and solar cells. Opt. Mater. 96, 109296 (2019).