Informace o publikaci
Quantum-mechanical analysis of H7LaNi5-xSnx
| Autoři | |
|---|---|
| Rok publikování | 2025 |
| Druh | Konferenční abstrakty |
| Fakulta / Pracoviště MU | |
| Citace | |
| Popis | Investigating hydrogen sorption in hydride-forming materials is essential for advancing a wide range of industrial technologies. Among such materials, LaNi5 is a common candidate due to its ability to accommodate multiple hydride phases. Upon full hydrogenation, LaNi5 forms the stable hydride phase LaNi5H7. Its properties such as lowering absorption and desorption pressures and enhancing resistance to repeated cycling can be improved through partial substitution. In this work, we focused on LaNi5-xSnx compounds. Quantum-mechanical approaches play a crucial role in investigating hydride formation, particularly given the difficulty of experimentally resolving the precise crystal structures of these compounds, which further complicates subsequent thermodynamic analyses. Complementary Density Functional Theory (DFT) calculations provide key insights into ground-state properties, including equilibrium lattice parameters, formation energies, electronic density of states, and charge density distributions. DFT calculations revealed that the compositions LaNi4.88Sn0.13 and LaNi4.38Sn0.63 exhibit the highest thermodynamic stability among the LaNi5-xSnx series. Increased Sn content in the investigated structures further influences the magnetic properties of the phases. The phase with a lower Sn concentration retains its magnetic character, whereas the phase with a higher Sn concentration becomes non-magnetic. These optimized structures subsequently serve as the basis for modeling the formation of the type H7LaNi5-xSnx hydrides. This provides insight into how partial substitution of Ni by Sn affects hydrogen uptake and the stability of the resulting hydride phases. In addition, the computational time requirements were analyzed with respect to the number of computational nodes and the internal parameters of the applied code, offering a practical perspective on the efficiency and scalability of such simulations. |