A New Family of Homo- and Heterometallic Manganese Complexes at High Oxidation States Derived from the Oxidation of MnII with CeIV: Syntheses, Structures, and Magnetic Properties

✍ Scribed by Cheng-Bing Ma; Ming-Qiang Hu; Hui Chen; Chang-Neng Chen; Qiu-Tian Liu

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 995 KB
• Volume: 2011
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.201100719

✦ Synopsis

Abstract

A series of homo‐ and heterometallic manganese(III or IV) clusters, Mn~2~O~2~(pybim)~4~~4~·11H~2~O [1; pybim = 2‐(2‐pyridyl)benzimidazole], [Mn~3~O~4~(bipy)~4~(H~2~O)~2~][Ce(NO~3~)~5~(H~2~O)][NO~3~]~2~·2H~2~O (2; bipy = 2,2′‐bipyridine), [Mn~2~Ce~3~O~6~(pta)~6~(NO~3~)~2~(dmf)~4~]·H~2~O (3; Hpta = p‐toluic acid), and [Mn~8~CeO~8~(pta)~12~(dmf)~4~] (4), were prepared by the reaction of simple Mn^2+^ salts with (NH~4~)~2~[Ce(NO~3~)~6~] under different experimental conditions. The single‐crystal X‐ray diffraction analyses established that these complexes possess inorganic cores that have various structural topologies, which range from the [Mn~2~O~2~]^4+^ rhomb, a Mn~3~ triangle within [Mn~3~O~4~]^4+^, and the nonplanar [Mn~8~O~8~]^8+^ loop that centrally traps a Ce^4+^ ion to the [Mn~2~Ce~3~O~6~]^8+^ cage that contains a Mn~2~Ce~3~ trigonal bipyramid. The solid‐state magnetic susceptibility studies revealed that these four complexes possess distinctly different magnetic properties, namely, both 1 and 2 show strong antiferromagnetic interactions between the Mn^IV^ centers, whereas 3 is weakly antiferromagnetic, and 4, however, has predominantly ferromagnetic interactions.