Effect of Structural Isomerism on Magnetic Dynamics: from Single-Molecule Magnet to Single-Chain Magnet

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• 作者：Ting-Ting Wang ; Min Ren ; Song-Song Bao ; Bin Liu ; Li Pi ; Zhong-Sheng Cai ; Ze-Hua Zheng ; Zhong-Li Xu ; Li-Min Zheng
• 刊名：Inorganic Chemistry
• 出版年：2014
• 出版时间：March 17, 2014
• 年：2014
• 卷：53
• 期：6
• 页码：3117-3125
• 全文大小：517K
• 年卷期：v.53,no.6(March 17, 2014)
• ISSN：1520-510X

文摘

This Paper reports the first examples of O鈥揚鈥揙 bridged Mn₂(salen)₂ (salen = N,N'-bis(salicylidene)ethylenediamine) chain compounds, namely, [Mn₂(salen)₂(2-FC₆H₄PO₃H)](ClO₄)路1/2CH₃OH (1) and [Mn₂(salen)₂(4-FC₆H₄PO₃H)](ClO₄) (2). The phosphonate ligands adopt a syn-anti bidentate bridging mode in 1 and a syn-syn bidentate bridging mode in 2, originated from the isomeric phosphonate ligands. The different bridging modes cause a significant change in the Mn鈥揙路路路O鈥揗n torsion angle over the O鈥揚鈥揙 bridge, which are 96.6 and 1.9掳 for 1 and 2, respectively. As a result, the antiferromagnetic (AF) exchange couplings mediated through the O鈥揚鈥揙 pathway are extremely weak in 1, and the overall magnetic behaviors are dominated by the Mn₂(salen)₂ moieties. Single-molecule magnetic behavior is observed in 1. For compound 2, the AF interaction over the O鈥揚鈥揙 bridge is much stronger. The coexistence of metamagnetism and single-chain magnetic behavior is observed for 2.