http://202.83.167.189/index.php/Nucleus/issue/feedThe Nucleus2026-08-25T09:05:44+05:00Dr. Maaz Khan (Editor-in-Chief)editorinchief@thenucleuspak.org.pkOpen Journal Systems<p><em>The Nucleus</em> is a well-established, open-access, peer-reviewed multidisciplinary scientific journal that has been in publication since 1964. The journal offers free access to all its content, both electronically and in print, ensuring that research is widely available to the public without any cost barriers. It is accredited as Y-category journal by the Higher Education Commission (HEC), and published biannually. <em>The Nucleus</em> invites research scholars, faculty members, and academicians from various disciplines, particularly in the natural and applied sciences, to submit their original research manuscripts. The journal is committed to promoting flawless and unbiased research, adhering to international publishing standards. The publisher also actively promotes published articles worldwide through various media channels, in line with open access regulations, ensuring that the research reaches a broad audience.</p> <p>The motto of <em>The Nucleus</em> reflects its dedication to transparency, integrity, and the promotion of high-quality research.</p> <p><strong><!--a href='#' id="fullscope" >Read More >></a--></strong></p>http://202.83.167.189/index.php/Nucleus/article/view/1520Structural, Electronic, Magnetic, and Thermoelectric Properties of Cr-doped DPs Cs2GeX6 (X= Cl, Br): DFT calculations2026-07-01T08:42:07+05:00S. Abbassultanabbas8285@gmail.comM. A. Khangreatkhan17@gmail.comS. Niazshanawersi@gmail.com<p>Physical properties of chromium-doped halide double perovskites (DPs) Cs<sub>2</sub>GeX<sub>6</sub> (X= Cl, Br) are estimated with respect to the DFT-based software Wein2k. These materials can be selected for solar cells and photovoltaics owing to their non-toxicity and ecological sustainability. Density functional theory (DFT) calculations investigate the physical characteristics of halides A<sub>2</sub>BX<sub>6</sub> (A=Cs; B=Ge; X=Cl, Br), both pure and Cr-doped, which can potentially be applied to thermoelectric applications. Formation conditions and tolerance factors ensure the material's structural and thermodynamic feasibility. The band gap of the material Cs<sub>2</sub>GeCl<sub>6</sub> is 4.5 eV; the same for the doped one Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Cl<sub>6</sub> is 4.1 eV; the band gap of the material Cs<sub>2</sub>GeBr<sub>6</sub> is 3.0 eV, while that of the doped material Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Br<sub>6</sub> is 2.5 eV. Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Cl<sub>6</sub> and Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Br<sub>6</sub> have indirect band gaps, respectively. Furthermore, when the chromium doping ratio increases, so do the equilibrium lattice parameters of Cs<sub>2</sub>GeCl<sub>6</sub> and Cs<sub>2</sub>GeBr<sub>6</sub>. Cs<sub>2</sub>GeCl<sub>6</sub>: 10.32 Å, Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Cl<sub>6</sub>: 10.55 Å, and Cs<sub>2</sub>GeBr<sub>6</sub>: 10.65 Å, Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Br<sub>6</sub>: 10.85 Å are the calculated lattice parameters. Both compounds have the same total magnetic moment values with 25% Cr doping for Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Cl<sub>6 </sub>and Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Br<sub>6</sub>. As a result, all of the halides investigated are commonly employed in thermoelectric devices. Thermal conductivity, electrical conductivity, and the Seebeck coefficient are also used to investigate thermoelectric properties. The computed values for PF at 200 K are PF=1.90 and 1.85 , and PF=3.98 and 4.09 at 800 K are measured for Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Cl<sub>6 </sub>and Cs<sub>2</sub>Ge<sub>0.75</sub>Cr<sub>0.25</sub>Br<sub>6</sub>, respectively, highlighting their importance in thermoelectric applications. The Seebeck coefficient value drops as temperature increases.</p>2026-08-24T00:00:00+05:00Copyright (c) 2026 The Nucleus