Low-Coordinate Building Blocks for Cyanide-Based Single-Molecule Magnets

化学结构、动力学和机制项目支持密苏里大学圣路易斯市的Stephen Holmes教授。Louis研究了模块构建模块及其多核衍生物的磁性行为差异，作为过渡金属取代，连接和辅助配体，配位环境和自旋基态简并的函数。将探索单离子磁各向异性如何转化为一系列结构相关的双核和三核配合物所表现出的磁性能。将构建几个3-和4-配位分子结构单元，其中包含顺磁中心和轨道简并自旋基态；立体要求高的配体将加强这种几何形状，并允许有效的自旋轨道耦合相互作用。阐明单离子磁相互作用如何帮助形成多核复合物的起源，这些复合物自旋基态具有特别大的零场分裂，这是这项工作的目标。几种含有线性M-X-M桥的双金属和三金属单分子磁性配合物（SMMs），其中X =氰化物和1,4-丁二苯乙烯，将使用有目的地设计的前体配合物进行探索。结构-性质关系将被绘制并用于完善我们对如何设计和使用轨道简并和各向异性自旋中心来构建smm的理解。提出的研究将影响在一系列信息存储技术中使用可溶性过渡金属配合物作为可切换组件的努力。拟议的国内/国际合作与交流将允许参与的学生发展科学的全球视野，建立潜在的终身合作，并提供目前在其本国机构无法获得的互补技能和专业知识的机会。对大圣路易斯地区众多本科生、ACS SEED和区域STARS（学生和教师作为研究科学家）学生和高中教师的指导将继续成为研究工作不可或缺的一部分。

The Chemical Structure, Dynamics and Mechanisms Program supports Professor Stephen Holmes of the University of Missouri-St. Louis to investigate differences in magnetic behavior for modular building blocks and their polynuclear derivatives, as a function of transition metal substitution, linking and ancillary ligands, coordination environment, and spin ground state degeneracy. Efforts to understand how single-ion magnetic anisotropy translates into magnetic properties exhibited by a series of structurally related bi- and trinuclear complexes will be explored. Several 3- and 4-coordinate molecular building blocks containing paramagnetic centers with orbitally degenerate spin ground states will be constructed; sterically demanding ligands will enforce this geometry and allow for efficient spin-orbit coupling interactions. Elucidating origins of how single-ion magnetic interactions assist in the formation of polynuclear complexes that spin ground states with exceptionally large zero-field splittings are the goals of this effort. Several bi- and trimetallic single-molecule magnetic complexes (SMMs) containing linear M-X-M´ bridges, where X = cyanide and 1,4-butadiynylide, will be explored using purposefully designed precursor complexes. Structure-property relationships will be drawn and used to refine our understanding of how orbitally degenerate and anisotropic spin centers can be designed and used to construct SMMs. The proposed research will impact efforts to use soluble transition metal complexes as switchable components in a range of information storage technologies. Proposed domestic/international collaborations and exchanges will allow participating students to develop a global perspective of science, establish potentially life-long collaborations, and afford access to complementary skills and expertise currently unavailable at their home institutions. Mentorship of numerous undergraduate, ACS SEED, and regional STARS (Students and Teachers as Research Scientists) students and high school teachers within the greater St. Louis region will continue to be integral to research efforts.