charge-transfer transition. Between 4 and 320 K, the iron(II) is in the low-spin form in the majority of these compounds; high-spin exceptions are [Fe(dpya)3][ClO4]2 and [Fe(mbzimpy)2]Cl2. Other complexes show evidence of the onset of a spin transition near 40 °C, while the salt [Fe(bztpy)2][ClO4]2·CHCl3 is a well defined spin-crossover system. The low-spin complex [Fe(bzimpy)2][ClO4]2 was excited by irradiation
阳离子型[Fe(L NN)3 ] 2+和[Fe(L NNN)2 ] 2+的阳离子络合物已分离为Cl –,ClO 4 –或BF 4 –盐,其中L NN和L NNN表示二齿和三齿氮供体
配体。二齿
配体为2-(2'-
吡啶基)
苯并咪唑(pybtim),2-(2'-
吡啶基)-N-甲基
苯并咪唑(mpybzim);2-(2'-
吡啶基)
苯并噻唑(pybzt),
2,2'-二吡啶胺(dpya)和三齿二(2-
吡啶基甲基)胺(dpyma),2,6-双(
苯并咪唑-2'-yl)
吡啶(bzimpy),2,6-bis(N-甲基
苯并咪唑-2'-基)
吡啶(mbzimpy)和2,6-双(
苯并噻唑-2'-基)
吡啶(bztpy)。除了[Fe(dpya)3 ] [ClO 4 ] 2以外,所有这些FeN 6发色团在550 nm区域均显示强吸收,这被指定为
金属到
配体的电荷转移跃迁。在4至320 K之间,大多数这些化合物中的
铁(II)呈低自