Speaker
Description
Martin Friák1, Martin Zelený2,3, Martina Mazalová1, Ivana Miháliková1, Jiří Kamarád4, Jiří Kaštil4, Ilja Turek1, Oldřich Schneeweiss1, Mojmír Šob5,1
1 Institute of Physics of Materials, v.v.i., Czech Academy of Sciences, Žižkova 22, CZ-616 62 Brno, Czech Republic;
2 Institute of Materials Science and Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, Brno, 61669, Czech Republic;
3 Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, Prague, 12116, Czech Republic;
4 Institute of Physics, v.v.i., Czech Academy of Sciences, Na Slovance 2, Prague, 18221, Czech Republic
5 Department of Chemistry, Faculty of Science, Masaryk University, Kotlářská 2, CZ-611 37 Brno,Czech Republic;
We have performed a quantum-mechanical study of thermodynamic, elastic, magnetic and structural properties of four different ferrimagnetic states in Ni1.9375Mn1.5625Sn0.5 martensite. They are modeled by the four-layer modulated 4O structure with Mn-excess atoms randomly distributed in Ni and Sn sublattices. The Mn atoms at the Ni sublattice turn out to be decisive for both thermodynamic and magnetic properties. A reversal of the orientation of their local magnetic moments has a huge impact on the properties of the whole system. The lowest-energy configuration exhibits anti-parallel local magnetic moments of these Mn atoms with respect to the orientation of the total magnetic moment. By testing both elastic properties and phonon modes we conclude that the lowest-energy state is mechanically stable. Magnetic as well as vibrational properties of individual atoms are found to be very sensitive to the chemical disorder. For details see M. Friák et al., Intermetallics (2022) accepted for publication.
Acknowledgments:
The authors acknowledge the Czech Science Foundation for the financial support received under the Project No. 20-16130S entitled “Multifunctional properties of powdered Ni-Mn-Sn Intermetallics”. Computational resources were made available by the Ministry of Education, Youth and Sports of the Czech Republic under the Project of the IT4Innovations National Supercomputer Center (project “e-Infrastructure CZ-LM2018140”) within the program Projects of Large Research, Development and Innovations Infrastructures and via the CESNET (Project No. LM2015042) and CERIT-Scientific Cloud (Project No. LM2015085).
