固体阶段的分子间质子转移:一种罕见的晶体到晶体转换的例子,从氧到氧桥梁的铁(III) 基于分子的磁铁
Donatella Armentano1, Giovanni De Munno, Teresa F Mastropietro
1Dipartimento di Chimica, Università della Calabria, via P. Bucci, 87036 Rende, Cosenza, Italy.
Journal of the American Chemical Society
|August 4, 2005
概括
一个新的铁 (III) 化合物在固体阶段经历了分子间的质子转移,将桥转化为桥. 这种结构变化导致晶体材料呈现磁性约70K左右.
科学领域:
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
背景情况:
- 铁 (III) 化合物以其多样化的结构图案和磁性特性而闻名.
- 固态无机化合物中的质子转移反应对于理解反应性和相位过渡至关重要.
- 这项研究重点研究了一种新型的mu-hydroxo铁 (III) 复合物,它有可能产生有趣的磁性行为.
研究的目的:
- 为了合成和表征一种新的mu-hydroxo铁 (III) 化合物.
- 为了研究分子间质子转移在固体阶段的发生和后果.
- 探索产生的材料的磁性特性和排序.
主要方法:
- 合成{EtNH3[Fe2(ox) 2Cl2(mu-OH) ].2H2O} 的一个化合物.
- 在质子转移之前和之后确定固态结构的X射线晶体学.
- 测量磁性易感度以调查磁性排序.
主要成果:
- 一种新的mu-hydroxo铁 (III) 化合物已成功合成和表征.
- 在固态中观察到从氧桥向水分子的分子间质子转移.
- 质子转移导致晶体化合物的形成,一个mu-oxo桥取代了mu-hydroxo桥.
- 初始和最终的晶体形式都在约70K时由于旋转倾斜而表现出磁性排序.
结论:
- 固相分子间质子转移可以导致协调化合物的结构转变.
- 观察到的转化产生了一个稳定的,晶体的mu-oxo铁 (III) 化合物.
- 这些化合物的磁顺序归因于旋转倾斜,发生在相对较高的温度下.
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