Magnetic properties and molecular structure of a binuclear alternative bridged Cu(II)Re(IV) complex containing a macrocyclic ligand

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• 作者：Alina Bie艅ko^a ; ^{alina.bienko@chem.uni.wroc.pl" class="auth_mail} ; Rafa艂 Kruszy艅ski^b ; Dariusz Bie艅ko^c
• 关键词：Building block ; Bimetallic complexes ; Alternating chain ; Exchange interaction ; Ferrimagnetic properties
• 刊名：Polyhedron
• 出版年：17 June 2014
• 年：2014
• 卷：75
• 期：Complete
• 页码：1-8
• 全文大小：1287 K

文摘

Two novel macrocyclic compounds, the heterobimetallic complex {(CuL_伪)[ReCl₄(ox)]}_n (class="boldFont">1) and the mononuclear complex [CuL_伪]·2ClO₄ (class="boldFont">2) (where L_伪 = N-meso-5,12-Me₂-7,14-Et₂-[14]-4,11-dieneN₄), have been synthesized and their crystal structures were determined by the single-crystal X-ray diffraction technique. Complex class="boldFont">1 crystallizes in the monoclinic space group P2₁/c, whereas class="boldFont">2 crystallizes in the monoclinic space group P2₁/n. The [CuL_伪]²⁺ macrocyclic cation in class="boldFont">1 is coordinated from above and below by [ReCl₄(ox)]²⁻ units through the chloro- and monodentate oxalato ligands, and this creates an alternating chloro-oxalato-bridged heterometallic Re^IV–Cu^II one-dimensional zig-zag chain. Their magnetic measurements were carried out over the temperature range 1.8–300 K using a Quantum Design SQUID magnetometer (MPMSxL-5 type). Compound class="boldFont">1 behaves like a ferrimagnetic Cu^II–Re^IV dimetallic chain with two intrachain antiferromagnetic coupling parameters and strong single-ion anisotropy, D(Re) = 109 cm⁻¹. Compound class="boldFont">2 shows weakly interacting paramagnetic centers in the crystal lattice. The effects of hydrogen bonds mediating the magnetic exchange interactions on the spin density have been evidenced by DFT calculations.