在 bis ((o-semiquinonato) 铜中对铁对抗铁磁性交换比的联体效应 (II)
Victor I Ovcharenko1, Elena V Gorelik, Sergey V Fokin
1International Tomography Center, Russian Academy of Sciences, 3A Institutskaya Street, 630090 Novosibirsk, Russian Federation. Victor.Ovcharenko@tomo.nsc.ru
Journal of the American Chemical Society
|August 7, 2007
概括
合成了具有特定磁性特性的新铜复合物. 添加额外的连接物显著改变了它们的磁性行为,影响了基本状态的多重性和交换相互作用.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 量子化学 是一个量子化学.
背景情况:
- 合成涉及铜 (II) 和半 (SQ) 连接体的新型异质复合体.
- 这些复合体表现出显著的分子内铁磁和反铁磁交换相互作用.
研究的目的:
- 为了合成和表征新的混合配体异体复合体.
- 为了研究额外的连接体对铜的磁性属性的影响 (II) 二氧化 (semiquinonato) 复合物.
- 使用量子化学方法分析磁结构相关性.
主要方法:
- 合成的异体复合物:[Cu(SQ) 2Py].C7H8,Cu(SQ) 2DABCO,和[Cu(SQ) 2NIT-mPy].C6H6.6.
- 进行X射线衍射和磁化学研究.
- 磁结构相关性的量子化学分析.
主要成果:
- 合成了三种具有较大的交换合参数的新型异体旋复合物 (能用J干 ≈ 100-300 cm(-1)).
- 证明了协调一个额外的连接体 (Py,NIT-mPy或DABCO) 极大地改变了磁性特性和基本状态的多重性.
- 量子化学分析显示,反铁磁交换相互作用能量对额外连接体和结构扭曲的性质具有很高的敏感性.
结论:
- 选择额外的连接体极大地影响铜 (II) 双 (II) 半酸复合体的磁性行为.
- 由连接体协调引起的结构变化是调整磁性质的关键.
- 这些发现为控制分子材料中的磁相互作用提供了洞察力.
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