MRI/RUI: Acquisition of a Powder X-Ray Diffractometer

RUI的这项重大研究仪器拨款支持购买粉末X射线衍射仪（XRD）。XRD是材料表征中非常有用的工具。它产生的晶格平面距离测量使未知晶体化合物的鉴定成为可能。XRD将通过识别从溶液中沉淀出来的单晶形式生长的化合物来加强新材料的有力研究计划，这种技术被称为助熔剂生长。一旦确定，这些单晶将使用现有的仪器在格林内尔，测量直流磁化，交流磁化率，电阻率，磁阻和热容的特点。这项研究是作为主要研究者，格林内尔大学的本科生和艾姆斯实验室的同事之间的强烈合作努力而进行的。XRD将支持的当前研究项目的例子包括稀土金属间化合物单晶的磁各向异性研究和单晶形式的强各向异性自旋玻璃的设计，用作测试自旋玻璃理论的模型系统。这些项目的成果将通过与学生合著的同行评审期刊出版物以及通过在国家会议上的发言广泛传播。因为研究总是与教学相结合，在格林内尔，XRD将有超出它所支持的研究项目的影响。学生将使用XRD与首席研究员合作研究，教师指导的独立学生项目，以及物理专业课程的实验。格林内尔学院已获得国家认可，其成功的努力，以增加通过新科学项目等计划在科学代表性不足的群体保留。XRD将有助于扩大代表性不足的群体在其教育和研究培训中对研究质量仪器的接触。

This Major Research Instrumentation RUI grant supports acquisition of a powder x-ray diffractometer (XRD). The XRD is an extremely useful tool in materials characterization. The lattice plane distance measurements it yields make possible the identification of unknown crystalline compounds. The XRD will enhance a vigorous research program in novel materials by identifying compounds grown in single crystal form by precipitation from solution, a technique known as flux growth. Once identified, these single crystals will be characterized using an existing instrument at Grinnell, which measures dc magnetization, ac susceptibility, resistivity, magnetoresistivity, and heat capacity. This research is pursued as a strongly collaborative effort between the principal investigator, undergraduates at Grinnell, and colleagues at Ames Laboratory. Examples of current research projects the XRD will support include studies of magnetic anisotropy in rare earth intermetallic single crystals and the design of a strongly anisotropic spin glass in single crystal form, to be used as a model system for testing spin glass theories. The results of these projects will be disseminated broadly through peer-reviewed journal publications with student co-authors and through presentations at national conferences. Because research is always blended with teaching at Grinnell, the XRD will have impact beyond the research projects that it supports. Students will use the XRD in collaborative research with the principal investigator, faculty-mentored independent student projects, and experiments in courses taken by physics majors. Grinnell College has attained national recognition for its successful efforts to increase the retention of under-represented groups in science through programs such as the New Science Project. The XRD will help to broaden the exposure of under-represented groups to research quality instrumentation in their education and research training.