一个棒家族:合成,结构和磁性特性
Gopalan Rajaraman1, Muralee Murugesu, E Carolina Sañudo
1Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
Journal of the American Chemical Society
|November 26, 2004
概括
新的复合物被合成和表征. 综合体1展示了单分子磁铁的行为,显示了先进磁性应用的潜力.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 磁电化学 磁电化学 磁电化学
背景情况:
- 混合价值金属三角形是新型磁性材料的前体.
- 像1,1,1-tris(hydroxymethyl) ethane (H(3) thme) 和1,1,1-tris(hydroxymethyl) propane (H(3) tmp) 这样的三足体连接体可以形成复杂的结构.
研究的目的:
- 为了合成和表征新的杆状复合物.
- 为了研究这些复合物的磁性,包括基态旋转和磁性行为.
主要方法:
- 混合价值三角形与酸中的三脚联体的反应.
- 可变温度直流 (dc) 磁感应度测量.
- 密度函数理论 (DFT) 的计算.
- 单晶歇斯底里循环和放松测量.
主要成果:
- 合成了一个由边缘共享三角形衍生的杆状复合物的家族.
- 复合物1 ([Mn{12}O{4}OH{2}PhCOO{12}thme{4}py{2}) 显示一个S=7的基本状态,并表现出单分子磁铁 (SMM) 的行为.
- 复合体2 ([Mn(8) O(4) ((CH(3)) ((3) CCO(2)) ((10) ((thme) ((2))) 的基本状态是S=6.
- 复合体3 ([Mn(7) O(2) ((PhCO(2)) ((9) ((thme) ((2) ((py) ((3))) 的基本状态是S=7.
- 复合体4 ([Mn(6) ((((CH(3)) (((3) CCO(2)) ((8) (((tmp) ((2))))) 具有合适的S = 3基本状态,其中DFT表明S = 4.
- 复合体5 ([Mn(6) ((CH(3) CO(2)) ((6) ((thme) ((2) ((H(2) tea) ((2))) 显示没有令人满意的匹配,DFT表明S = 0.
结论:
- 合成的复合物表现出不同的磁性特性.
- 综合体1被确定为单分子磁铁,突出其分子磁性的潜力.
- 结构和磁性特性受到连接物选择和金属集群架构的影响.
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