Syntheses, structures, and magnetic properties of discrete cyano-bridged heterodinuclear complexes composed of MnIII(salen)-type complex and MIII(CN)6 anion (MIII = Fe, Mn, and Cr)

Reacting [MnIII(5-TMAM(R)-salmen)(H2O)2](ClO4)3·H2O with [MIII(CN)6]3− moieties yields a series of discrete cyano-bridged heterodinuclear complexes, [MnIII(5-TMAM(R)-salmen)(H2O)MIII(CN)6]·7H2O·MeCN (where 5-TMAM(R)-salmen = (R)-N,N′-(1-methylethylene)bis(5-trimethylammoniomethylsalicylideneiminate; M = Fe (1), Mn (2), and Cr (3)). dc magnetic susceptibility and magnetization studies on powdered samples showed that the MnIII(5-TMAM(R)-salmen) moiety had significant uniaxial anisotropy and that [MIII(CN)6]3− moieties of 1 and 2 had magnetic anisotropy due to unquenched orbital angular momenta, which significantly affects the magnetic behavior of this system. Frequency-dependent ac susceptibility signals indicated that slow magnetic relaxation was occurring, meaning that 1 and 2 behave as single-molecule magnets.

Graphical abstractThe reaction of [MnIII(5-TMAM(R)-salmen)(H2O)2](ClO4)3·H2O with [MIII(CN)6]3− (M = Fe (1), Mn (2), and Cr (3)) yielded a series of cyano-bridged discrete heterodinuclear complexes. Studies of dc magnetic susceptibility and magnetization on powdered samples showed that the MnIII(5-TMAM(R)-salmen) moiety had significant uniaxial anisotropy and that [MIII(CN)6]3− moieties of 1 and 2 had magnetic anisotropy due to unquenched orbital angular momenta, which significantly affect the magnetic behavior of the complexes. Frequency-dependent ac susceptibility signals indicate that 1 and 2 exhibit slow magnetic relaxation and, thus, behave as SMMs.Figure optionsDownload full-size imageDownload as PowerPoint slide