Solid State Chemistry of Crystalline and Glassy Chalcogenides

本项目涉及盐通量在广泛的硫系化合物类中导致新材料的有效性。控制化学反应系统和通过开发一般合成方法发现新材料的能力定义了我们理解复杂固体中化学，晶体结构和性质之间关系的主要挑战之一。该项目侧重于复杂金属铜磷酸盐和铜酸盐材料。这门课继续呈现出奇妙的科学挑战，它与许多技术应用广泛相关。我们期待新材料具有有趣和潜在有用的物理性质，如半导体行为，二次谐波产生，玻璃形成，可逆相变晶体到玻璃的转变。该项目探索(a)多硫代磷酸锂助熔剂(b)碱金属多硫代砷酸盐和多硒代砷酸盐助熔剂(c) 31P核磁共振波谱以研究多硫代磷酸盐助熔剂和在这种助熔剂中进行的反应。(d)最后，我们将调查和研究在某些元素组合中发生的玻璃形成系统的性质。这个项目将在一个有价值的知识话语中教育和暴露学生。参与该项目的学生将接受固态化学和材料研究方面的优秀培训。他们将直接意识到他们的材料与科学技术的相关性。拟议的活动将努力为学生提供一个有意义的、连贯的研究和教育计划，以便他们作为未来的独立科学家，能够产生、处理和操纵新型固态材料。在美国，提供这类培训的实验室相对较少。本科生也参与这种类型的研究，这对他们的大学实验室经历和未来的职业选择有持久的影响。新材料是许多先进技术和产品的核心。该项目旨在利用新颖的合成技术发现新材料，并训练学生进行这类研究。这种材料属于更广泛的半导体类别，有望具有有趣和潜在有用的物理特性。这些特性包括可控电导率、光活性、玻璃形成特性和相变特性。该项目将研究与非易失性数据存储和计算机内存应用相关的新相变材料。所开发的方法和获得的见解与不寻常固体的形成、化学和性质有关，可以推动或促进有用的技术，从而可以对科学做出重要贡献，并可能对许多技术产生重大影响，进而对美国经济产生重大影响。参加这种类型的研究生和本科生将有广泛的未来职业选择，并将在就业市场上非常有竞争力。这项研究的结果将向公众公布。通过传播媒体、网络和期刊出版物广泛传播科学成果和知识，将有助于提高公众对科学的理解和欣赏。

This project deals with the effectiveness of salt fluxes to lead to new materials in the broad chalcogenide class of compounds. The ability to control chemical reaction systems and to discover new materials through developing general synthetic methodologies defines one of the main challenges to our understanding of the relationships between chemistry, crystal structures, and properties in complex solids. The project focuses on complex metal chalcophosphate and chalcoarsenate materials. This class continues to present marvelous scientific challenges and it is broadly relevant to many technological applications. We anticipate new materials with interesting and potentially useful physical properties such as semiconducting behavior, second harmonic generation, glass formation, and reversible phase-change crystal to glass transitions. The project explores (a) lithium polythiophosphate fluxes (b) alkali metal polythioarsenate and polyselenoarsenate fluxes (c) 31P NMR spectroscopy to investigate poly-thiophosphate fluxes and reactions performed in such fluxes. (d) Finally, we will investigate and study the properties of glass forming systems occurring in certain element combinations. The project will educate and expose students in a worthwhile intellectual discourse. The students working on the project will receive outstanding training in solid-state chemistry and materials research. They will acquire a direct awareness of the relevance of their materials to science and technology. The proposed activity will strive to furnish a meaningful, coherent research and education program for students so that they, as future independent scientists, are able to generate, handle and manipulate novel classes of solid-state materials. Relatively few laboratories in the US provide the type of training proposed. Undergraduate students also participate in this type of research, which has a lasting impact on their college laboratory experience and future career choices. %%%New materials are at the core of many advanced technologies and products. This project seeks to discover new materials using novel synthesis techniques and to train students in the discourse of this type of research. The materials belong to the broader class of semiconductors and are expected to possess interesting and potentially useful physical properties. These include controllable electrical conductivity, photoactivity, glass forming properties and phase-change properties. This project will investigate new phase-change materials relevant to non-volatile data storage and computer memory applications. The methodology developed and the insights gained relevant to the formation, chemistry and properties of unusual solids, could enable or facilitate useful technologies and thus could make an important contribution to science and could have a significant impact in a number of technologies and by extension on the US economy. Graduate and undergraduate students participating in this type of will have a wide range of future career choices, and will be very competitive in the job market. The results of this research will be available to the public. The broad dissemination of scientific results and knowledge through the communications media, the web and journal publications will help enhance the public's scientific understanding and appreciation.