Discovery Research For New Optical Materials

This project utilizes the material genome initiative (MGI) approach to aid in the discovery of new optical compounds to be used in scintillators at an accelerated rate. Novel materials for optical applications, such as luminescent scintillators, are desired for the improvement of properties. Using density functional theory (DFT) calculations, new single-crystal scintillating materials can be optimized leading to more efficient scintillation. Two existing compounds in the quaternary system Na-O-Si-Y were chosen and further modified using substitutions into proposed structures that can be investigated. The two original compounds, NaO4SiY, and NaO26Si6Y9, were chosen and modified because of their already high density. The target modifications include substituting yttrium for lanthanum, sodium for potassium and yttrium for lanthanum, and lastly yttrium for zirconium and sodium for potassium. The potassium substitution allows the structure to slightly expand to yield more realistic bond distances. This yields a total of 8 structures, with 6 being proposed structures derived from modifications for study. Figure 1 shows the band gap for the NaO4SiY. Following the DFT calculations, it was discovered that some stoichiometries form metallic compounds which may not be useful for optical applications. Current work is focused on synthetic investigations of these stoichiometries