Unlocking the Power of Group 16 (and 17) in the Solid State

Solid-state materials chemistry focuses on metals and cationic substitutions, particularly those in oxide ceramics. Relative to oxides, chalcogenides and mixed anion systems have been relatively underexplored. The Macaluso Research Group aims to uncover the structural and electronic role of Groups 16 and 17 elements in solid-state materials. We employ laboratory X-ray diffraction, synchrotron and neutron scattering to elucidate local and average crystal structures. We use diffuse reflectance spectroscopy to determine band gaps, and we use first-principles calculations and photoelectron spectroscopy to characterize the electronic structure of chalcogenide and mixed-anion systems. Our work demonstrates the following: 1) how the optical properties of CaCe2S4 can be controlled by elemental composition, and 2) how the local and average crystal structures of mixed anion systems - PbVO3Cl and Cd2Nb2O7-xSx, contribute to ferroelectric and thermochromic behavior. These findings have broader implications in the strategic exploration of mixed-anion materials.