experimentally establish a link between Heisenberg spin exchange and chemical reactivity. The acceptors are members of the oxo/hydroxo-biscarboxylato class of dinuclear Fe(III) compounds, where protonation of the oxo bridge provides a means for modulating the magnitude of spin exchange within the cluster. Photoexcitation of solutions containing Ru(II) polypyridyl sensitizers and the Fe(III) complexes results in
为了在实验上建立海森堡自旋交换与
化学反应性之间的联系,已经研究了光敏剂与交换偶联的过渡
金属配合物之间的双分子猝灭。受体是双核Fe(III)化合物的oxo / hydroxo-biscarboxylato类成员,其中oxo桥的质子化提供了一种调节簇内自旋交换强度的手段。含有Ru(II)聚
吡啶基敏化剂和Fe(III)配合物的溶液的光激发导致猝灭Ru(II)发色团的(3)MLCT激发态的发射;纳秒级时间分辨的吸收测量结果表明,淬灭部分地通过电子转移发生。通过改变桥联
羧酸酯以提供一系列[Fe(2)O(H)(O( 2)CR)(2)(Tp)(2)](n)(+)(n = 0、1、2)。电
化学测量显示整个系列中簇还原电位的位移大于500 mV(即R = CH(3)到CF(3)),而可变温度磁化率测量表明
金属中心之间的自旋交换具有相应的不变性(对于H = -2JS(1).S(2),J(氧代)= -119 +/-