Affiliation:
1. State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 P.R. China
2. School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 P.R. China
3. Department of Criminal Investigation Fujian Police College Fuzhou Fujian 350007 P.R. China
Abstract
AbstractWe report a trinuclear iron(III) cyanido‐bridged complex trans‐[CpMe3FeIII(dppe)(CN)]2[FeIII(LN4)][PF6]4 (2[PF6]4) as the oxidation product of binuclear complex [CpMe3(dppe)FeIICN‐FeIII(LN4)][PF6] (1[PF6]) (CpMe3=1, 2, 4‐trimethyl‐1,3‐cyclo‐pentadienyl, dppe=1,2‐bis(diphenylphosphino)ethane, LN4=pentane‐2,4‐dione‐bis(S‐methylisothiosemicarbazonato). Complex 1[PF6] possesses an intermediate‐spin five‐coordinated FeIII (S=3/2) which couples antiferromagnetically to the π‐radical ligand (L⋅N4)2− and shows a LMCT (ligand to metal charge transfer) transition from (L⋅N4)2− to FeIII and the FeII→FeIII MMCT transition. Upon oxidation of 1[PF6], (L⋅N4)2− loses one electron to be the strong electron‐attracting ligand (LOxN4)− and the intermediate‐spin five‐coordinated FeIII (S=3/2) becomes a low‐spin six‐coordinated FeIII (S=1/2) in 2[PF6]4. Also interestingly, 2[PF6]4 presents the coexistence of three different spin states (one S=3/2 and two S=1/2) and an uncommon FeIII→(LOxN4)− MLCT transition, confirmed by the experimental results and supported by the TDDFT calculations.
Funder
National Natural Science Foundation of China
Subject
General Chemistry,Catalysis,Organic Chemistry