(E)

1. New Polar Chalcophosphates with Strong SHG ResponseMercouri G. Kanatzidis, Northwestern University, DMR 0801855 This NSF funded research investigates new polar inorganic solid state materials for applications as Non Linear Optical (NLO) materials. In general, asymmetric inorganic polymer thin films with highly polarizable bonds exhibit strong nonlinear optical behavior and are used in tunable, coherent IR lasers that probe the electronic or structural properties of molecules or surfaces. We discovered the novel quaternary salts AZrPSe6; A = K+, Rb+, Cs+ which tend to crystallize as micro-needles. The crystal structure is non-centrosymmetric consisting of highly polarizable, covalently bonded P and Se atoms. So the AZrPSe6 compounds can generate a second harmonic beam in the crystal doubling the frequency of incident light. For CsZrPSe6, the intensity of this second harmonic generation (SHG) response was found to be 15 × stronger than that produced by a comparable commercial NLO material AgGaSe2. These salts are also optically transparent from the mid- to the near-IR region, which gives them potential for use in a broad range of applications, from broadband communication to medical devices. (E) (A) SEM image of needle shaped micro-crystals of KZrPSe6. (B) Non-centrosymmetric structure of KZrPSe6 : Molecular view along the [100] direction. (C) View of [ZrPSe6]- anion along the chain axis. (D) Polymeric 1/∞[PSe3-] chain acting as a backbone holding the Zr4+ ions together. (E) Strong SHG response from AZrPSe6.

2. New Polar Chalcophosphates with Strong SHG Response Mercouri G. Kanatzidis, Northwestern University, DMR 0801855 The metals chalcophosphates investigated in this project are an excellent class of materials to investigate as novel semiconductor materials with potential applications in nonlinear optical, solid state lighting based on inorganic phosphors, photovoltaic etc. The research in quest for these materials gives the undergraduate, graduate student and postdoc members of this community an excellent exposure and extensive training in fundamental solid state inorganic synthesis, crystallography and many other techniques needed to characterize inorganic semiconductors. This particular NSF funded research project reported in this highlight gave birth to an exquisite class of inorganic polymer having very wide scope of technological applications as NLO semiconductors. The polar NLO active materials can have broad technological impact in areas like telecommunications, sensors, detection device and optoelectronic applications. Finally, in terms of societal impact this research will continue to serve the community by teaching fundamental solid state chemistry and discovering exotic materials in an effort to improve the quality of life. Media release on DMR-Award# Project work