Progress in modern condensed matter physics and the development of modern technologies in recent decades is inseparably connected with the studies of complex oxide materials, since in this class of compounds was discovered such important phenomena as high-temperature superconductivity, colossal magnetoresistance effect, the metal-insulator transition, charge and orbital ordering, ferroelectricity, magnetoelectric effect, spin crossover, etc. Neutron diffraction is the most direct and informative method of studying the magnetic ordering in crystal materials. Functional oxides of transition metals are convenient model systems for the study of basic rules of physical phenomena in oxide magnets, so new experimental data will be important to clarify modern concepts of the microscopic mechanisms of the formation of physical properties and phenomena observed in these compounds.
Tasks
During the project, it is planned to perform treatment of the experimental data obtained on the DN-6 diffractometer. Rietveld method will be used for data processing. Parameters of crystal and magnetic structure including interatomic distances, valence angles, and the formation of magnetically ordered phases, and basic dependencies will be obtained.
Preliminary schedule by topics/tasks
1st week (14/02-20/02) Introduction to project
2nd week (21/02-27/02) Introduction to FullProf Software
3rd week - 5th week (28/02-20/03) Work on the project
6th week (21/03-25/03) Report preparation
Required skills
Students should know the basic principles of condensed matter physics, be guided in the principles of diffraction methods, have basic skills of working with typical scientific software.
Acquired skills and experience
Students will obtain an experience of treatment of neutron diffraction data by means of FullProf software. They will obtain skills of calculating from experimental data the most important parameters of crystal and magnetic structure including parameters of the unit cell, interatomic distances, valence angles, magnetic moments, and basic dependencies of these parameters under extreme conditions.
Recommended literature
1. Kozlenko D.P., Kichanov S.E., Lukin E.V., Savenko B.N. “The DN-6 Neutron Diffractometer for High-Pressure Research at Half a Megabar Scale”, Crystals, 8 (2018) 331
2. Neutron powder diffraction by Richard M. Ibberson and William I.F. David, Chapter 5 of Structure determination form powder diffraction data IUCr monographphs on crystallography, Oxford scientific publications 2002
3. A. V. Belushkin, D. P. Kozlenko, and A. V. Rogachev, Synchrotron and neutron-scattering methods for studies of properties of condensed matter: Competition or complementarity? J. Surf. Invest. 5, 828 (2011).
