Chemistry & Biochemistry Seminar: By Dr. Tiglet Besara, "Flux Synthesis: Breeding Ground for Discovery of Novel Intermetallics"

Intermetallics are attractive due to their wide variety of properties; superconductivity, semiconductivity, topology, etc. Several methods exist to grow new materials, and we utilize one of them, flux growth, which produces naturally faceted crystals. In this talk, I will discuss the discovery of two different intermetallics with this method: SmMnBi₂, a candidate for topological semimetals, and MM’₂Zn₂₀, a candidate for thermoelectric materials.

In topological materials, the bulk is a bad conductor while the surface states are metallic with high mobility. The surface is also topologically protected; basically meaning that impurities have no effect on the conductivity. A plethora of materials have been discovered and I will talk about the growth and structure of SmMnBi₂ and compare it to similar compounds.

Thermoelectric materials are appealing due their ability to directly convert between heat and electricity. The main issue is that the physical parameters to determine thermoelectric performance work against one another. For achieving the optimum performance, hindering lattice vibration by forming cage structures in which heavy atoms can rattle is a plausible way. I will talk about the growth and structure of cage-structured MM’₂Zn₂₀ compounds.

Free