Crystallographic Gems to Link Materials' Properties: Stannides, Germanides, and Antimonides

University Of Texas At Dallas, Richardson TX

Investigators

Abstract

Non-Technical Abstract The search for magnetic and thermoelectric materials with desired properties relies on the discovery of new metal-based compounds, and also requires that the materials can be grown as high quality single crystals. The research strategy of this project, funded by the Solid State and Materials Chemistry program in the Division of Materials Research, is motivated by magnetocalorics for refrigeration, thermoelectrics for converting wasted heat to electricity, and magnetic materials for next generation quantum computing. This project provides training opportunities for undergraduate and graduate students in a multidisciplinary environment. They gain insights into the design of novel materials. The partnership between the research group and the scientific community fosters continued enhancement in science learning. The principle investigator's group also works with a high school team of students and industrial partners as part of the "Young Women in Science" group and "Nanoexplorers", pursuing materials science projects. Additionally, the Chan group performs hands-on materials science-related demonstrations for the general public. Technical Abstract Discovering new metal-based compounds and linking their chemical structures to magnetic, electrical, and thermal properties for energy applications is the goal of this research, which is supported by the Solid State and Materials Chemistry program in the Division of Materials Research. The growth of large single crystals is necessary to unequivocally determine the material's innate properties. With this award, the principle investigator studies several classes of materials containing lanthanide, mid-transition metals, and Group 14-15 elements. The motivation for this effort is to correlate the structural details to predict physical properties. The efforts focus on growing high quality single crystals of the Tb117Fe52Ge112 (Ln = Gd, Dy) and Ln30Ru4Sn31 structure types, which allows the study of structural complexity, complex magnetism, and low lattice thermal conductivity. In addition to studying structural phase stability of stannides and germanides, atomic displacement parameters are correlated with electrical resistivity as a testbed for predicting electrical properties of materials. Inspired by the emergence of spin glass and itinerant magnetism in Pr2Fe4Sb5, the magnetic and electrical properties of Ln2Fe4-xMxSb5 (Ln = La, Ce, Pr, Sm; M = Mn, Co, Zn) are also investigated. Compounds of this structure type are of particular interest because of the Fe-triangular subunits coupled with Sb-square nets, two features found in several highly correlated systems. Students involved in the proposed project will also have the opportunity to work with collaborators at other institutions and national laboratories. The principle investigator's entire research group is involved in mentoring students at different levels, including undergraduates throughout the academic year and high school students in the summer.