Magnetic molecular charge transfer complexes

Abstract

The charge transfer complex [Fe (C5Me5) magnetization in zero applied field and is a bulk ferromagnet. These three compounds possess the same structural motif, namely, linear chains of alternating cationic donors and anionic acceptors. The high temperature magnetic susceptibility obeys the CurieWeiss expression with e = +30, -1.0, and -1.2 K, respectively, and the latter pair of complexes possess weak antiferromagnetic coupling. The ferromagnet exhibits zero field Zeeman split 57Fe Mossbauer spectra with an internal field of 425.6 kOe at 4.23 K. INTRODUCTIONWe have deliberately sought to prepare a molecular-based ground state bulk ferromagnet since our observation that 1-D 1:1 [Fe(C5Me5)2]+.[TCNQ] -. ¥ exhibited metamagnetic behavior [ 1]. Using permethylated metallocenium cations we have prepared a series of charge transfer complexes with a variety of radical anion acceptors in order to elucidate the critical structure-function relationships that might ultimately lead to the preparation of a molecular-based ferromagnet. With the specific goal of increasing the spin density we sought a smaller planar radical anion and selected S = 1/2

Recent Progress of Organic Semiconductor Materials in Spintronics

“…In 1987, Sailesh et al [32] . discovered the organic‐inorganic charge transfer composite ferromagnetic material [FeCp* 2 ] ⋅+ [TCNE] ⋅− based on ferrocene and tetracyanoethylene.…”

“…In 1987, Sailesh et al [32] discovered the organic-inorganic charge transfer composite ferromagnetic material [FeCp* 2 ] • + [TCNE] •À based on ferrocene and tetracyanoethylene. The crystal structure shows that the decamethylferrocene radical cation as a donor and the TCNE radical anion as an acceptor form an alternating arrangement one-dimensional structure.…”