SPIN-CROSSOVER OF [Fe(Cl-BZIMPY)2](ClO4)2 INDUCED BY DEPROTONATION
SPIN-CROSSOVER OF [Fe(Cl-BZIMPY)2](ClO4)2 INDUCED BY DEPROTONATION
复制标题
去质子化诱导的 [Fe(Cl-BZIMPY)2](ClO4)2 自旋交叉
DOI：
--
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
W. Linert
中科院分区：
文献类型：
--
作者：
M. Enamullah;W. Linert
摘要配体4- cl -2,6-二（苯并咪唑-2′-酰基）吡啶（Cl-bzimpy;H2L）与过渡金属离子配位时起双齿齿作用，分离得到配合物[Fe(Cl-bzimpy)2](ClO4)2为固体。质子化常数（logK）在30:70 (v/v) H2O:EtOH条件下，离子强度为0.13M (KCl)，在室温下对游离配体和配合物进行了评价。配体与金属离子的配位导致苯并咪唑基亚胺氢的酸度增加。脱质子作用导致配合物的自旋态发生变化（变为低自旋态；HS→LS跃迁），并导致自旋交叉平衡常数（Ksc）降低。当HClO4加入到络合物溶液中时，观察到相反的自旋态位移，从而显示了该过程的可逆性。
Abstract The ligand 4-Cl-2,6-bis(benzimidazol-2′-yl)-pyridine(Cl-bzimpy;H2L) acts as a bidentate when coordinated with transition metal ions and the complex [Fe(Cl-bzimpy)2](ClO4)2 was isolated as a solid. The protonation constants (logK). The free ligand and the complex were evaluated in 30:70 (v/v) H2O:EtOH at room temperature and ionic strength of 0.13M (KCl). Coordination of the ligand to the metal ion leads to an increase of the acidity of the imino-hydrogen of the benzimidazole group. Deprotonation leads to a change in the spin-state (to the low-spin state; HS → LS transition) of the complex associated with a decrease in the spin-crossover equilibrium constant (Ksc). An opposite shift of spin-state is observed when HClO4 is added to the complex solution, thus showing the reversibility of the process.