交换合和磁性阻断在二皮里米迪尔基因桥接的迪兰化物复合体中
Selvan Demir1, Joseph M Zadrozny, Michael Nippe
1Department of Chemistry, University of California, Berkeley, 94720, United States.
Journal of the American Chemical Society
|November 1, 2012
概括
研究人员合成了新的双皮里米迪尔基因桥接的迪兰化物复合物. 这些复合体表现出强烈的磁性合和单分子磁体行为,在分子磁力学中具有潜在的应用.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 兰化物复合物因其独特的磁性特性而引起人们的兴趣.
- 根基桥梁复合体为强大的磁交换相互作用提供了途径.
- 单分子磁铁 (SMM) 对于开发高密度数据存储和量子计算至关重要.
研究的目的:
- 为了合成和表征新的二皮里米迪尔基因桥接的迪兰化物复合物.
- 为了研究兰坦化离子和二甲基之间的磁交换合.
- 探索这些复杂物作为单分子磁铁的潜力.
主要方法:
- 合成了三种新的迪兰化物复合物:[(Cp*(2) Ln) (((2) (((μ-bpym(•)))))) ((+) (Ln = Gd,Tb,Dy).
- 测量磁感应度 (dc) 以探测磁相互作用和行为.
- 分析磁性数据以确定合常数和放松动态.
主要成果:
- 在所有合成的复合物中都观察到强烈的兰化物(III) -双基 (Ln(III) -bpym(•-)) 交换合.
- 加多 (III) 复合体显示反铁磁合 (J = -10 cm (-1)) 与S = 13/2基态.
- (III) 和 (III) 复合物表现出单分子磁体行为,具有显著的放松障碍 (U () =44 () 2) 和87.8 () 3) 厘米 (-1),分别).
- 双 (III) 复合物在6.5K显示场冷却/零场冷却分歧和磁歇斯底里,表明磁放松缓慢.
结论:
- 双 Pyrimidyl 基作为一个有效的桥梁连接体,用于调解在 dilanthanide 系统中的强磁交换.
- 合成的Tb (III) 和Dy (III) 复合体显示出有希望的单分子磁体特性,这是由于具有很大的磁性异质性.
- 这些发现有助于设计新的分子磁性材料,在纳米技术中具有潜在的应用.
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