Directed Assembly of Molecular Cluster Magnets

这个奖在无机，生物无机和有机化学计划教授杰弗里R。位于伯克利的加州大学的Long博士正在开发合成氰根配位簇的一般策略，作为在高密度信息存储和量子计算中具有潜力的单分子磁体（SMM）。 利用有机封闭配体指导形成特定的氰根簇几何构型的能力将扩展到更高核数物种的合成，例如边心立方[（L-fac）8（Leq）12 M12 M '8（CN）24]n+和双立方[（L-fac）14 M7 M' 8（CN）24]n+簇。 将适当的顺磁性金属离子取代到这些簇中，导致基态高达S = 18，并且将靶向自旋高达S = 32的新物种。将具有大的轴向零场分裂的金属离子并入到这样的结构中将被追求作为产生单分子磁体所需的磁各向异性的手段。额外的工作将集中在进一步增强磁各向异性通过纳入第三行过渡金属中心轴承轨道角动量，如Ta（III），W（IV），Re（III），Re（V）和Os（IV）。 此外，使用重供体原子配体将被测试作为进一步增加与簇构建单元相关的单离子各向异性的手段。路线的线性集群与平行排列的个别离子各向异性轴的建议，是一种方法，通过杂金属取代打破对称性在高nucleity立方物种。一个磁性化学系列，其中线性桥连配体根据其磁交换耦合能力，将被建立作为一种手段，评估置换配体的氰化物具有较强的磁耦合。此外，这些配体中的某些可以促进电子转移到一定程度，使得能够合成具有通过双交换机制产生的良好隔离的高自旋基态的混合价配体桥接簇。这项研究的更广泛的影响包括合成技术的遗产，创造具有潜在技术重要性的新材料，以及在无机材料的合成和表征方面对博士后，研究生和本科生的教育和培训。作为一项相关的教育活动，PI将牵头在部门内创建材料化学专业。加州大学伯克利分校的化学教授

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program to Professor Jeffrey R. Long of the University of California at Berkeley is to develop general strategies for the synthesis of metallocyanide coordination clusters as single-molecule magnets (SMMs) that have potential in high-density information storage and quantum computing. The ability to utilize organic blocking ligands in directing the formation of specific metallocyanide cluster geometries will be extended to the synthesis of higher-nuclearity species, such as edge-centered cubic [(L-fac)8(Leq) 12M12M'8(CN)24]n+ and double-cube [(L-fac)14M7M'8(CN)24]n+ clusters. The substitution of appropriate paramagnetic metal ions into these clusters has led to ground states of up to S = 18, and new species with spins as high as S = 32 will be targeted. Incorporation of metal ions possessing a large axial zero-field splitting into such structures will be pursued as a means of generating the magnetic anisotropy requisite of a single-molecule magnet. Additional work will focus on further enhancing magnetic anisotropy through the incorporation of third-row transition metal centers bearing orbital angular momentum, such as Ta(III), W(IV), Re(III), Re(V), and Os(IV). Moreover, the use of heavy donor atom ligands will be tested as a means of further increasing the single-ion anisotropy associated with cluster building units. Routes to linear clusters with parallel alignment of the individual ion anisotropy axes are proposed, as is a method for breaking the symmetry in high-nuclearity cubic species via heterometal substitution. A magnetochemical series in which linear bridging ligands are ordered according to their magnetic exchange coupling ability, will be established as a means of evaluating replacement ligands for cyanide with stronger magnetic coupling. In addition, certain of these ligands may facilitate electron transfer to an extent that enables the synthesis of mixed-valent, ligand-bridged clusters with well-isolated high-spin ground states arising via a double exchange mechanism. The broader impacts of this research include a legacy of synthetic techniques, the creation of new materials of potential technological importance, and the education and training of postdoctoral, graduate, and undergraduate students in the synthesis and characterization of inorganic materials. As a related educational activity, the PI will take the lead in creating a materials chemistry major within the Dept. of Chemistry at UC Berkeley.