通过热,压力和电化学刺激对复合物的可逆切换:突然,完全,歇斯底里旋转交叉
Matthew G Cowan1, Juan Olguín, Suresh Narayanaswamy
1Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
Journal of the American Chemical Society
|November 9, 2011
概括
这项研究引入了一种可三重切换的复合物,[Co(II) ((dpzca) ((2)),表现出由温度,压力和氧化还原变化引发的可逆旋转交叉. 这种磁切换行为为先进的材料应用提供了潜力.
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:
- 旋转交叉 (SCO) 材料对分子开关和内存设备有兴趣.
- 众所周知, (II) 复合体表现出旋转交叉现象.
- 通过多种刺激控制SCO行为对于实际应用至关重要.
研究的目的:
- 合成和表征一种具有可切换磁性质的新型 (II) 复合物.
- 为了研究由温度,压力和氧化还原刺激引起的复合物的旋转交叉行为.
- 探索这个复合体作为多刺激响应材料的潜力.
主要方法:
- 综合和结构性特征 [Co(II) ((dpzca) ((2)) ] 复合体.
- 可变温度磁感应度测量以研究旋转交叉.
- 高压研究研究压力诱导的旋转转变.
- 氧化还原定位和磁性测量,以探索氧化还原触发的切换.
主要成果:
- [Co(II) ((dpzca) ((2)) ]复合体表现出高旋转 (HS) 和低旋转 (LS) (II) 状态之间的突然,可逆和歇斯底里旋转交叉.
- 旋转过渡实际上是由温度变化引发的 (T(1/2) ↓ = 168 K,T(1/2)↑ = 179 K).
- 该综合体展示了由压力和氧化还原刺激诱导的可逆旋转切换,使HS (II) 和LS (III) 之间的过渡成为可能.
结论:
- [Co(II) ((dpzca) ((2)) ] 复合体是一种可三重切换的SCO材料.
- 其独特的切换机制 (温度,压力,氧化还原) 突出显示了其对先进功能材料的潜力.
- 对HS和LS国家的结构性特征提供了对上合组织机制的洞察.
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