Synthesis and Magnetism of {[Cu(II)]2Ln(III)} Heterotrinuclear Complexes Bridged by N,N'-bis(3-Amino-2-methylpropyl)oxamidocopper(II)

• Published in: Synthesis and reactivity in inorganic and metal-organic chemistry Vol. 34; no. 6; pp. 993 - 1008
• Main Authors: Li, Yan-Tuan, Yan, Cui-Wei, Zhu, Chun-Yuan
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01.07.2004
• Subjects: Charge transfer; Cu(Meoxpn); ESR; Heterotrinuclear complexes; Spin-exchange
• ISSN: 0094-5714; 1532-2440
• DOI: 10.1081/SIM-120037522

Ten new μ-oxamido-bridged {[Cu(II)] 2 Ln(III)}-type heterotrinuclear complexes described by the overall formula Cu 2 (Meoxpn) 2 Ln(NO 3 ) 3 (Ln = Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er), where Meoxpn denotes the N,N′-bis(3-amino-2-methylpropyl)oxamido dianion, have been synthesized and characterized by elemental analyses, molar conductivity measurements, and spectroscopic (IR, UV, and ESR) characterization. Magnetic susceptibility (4.2-300 K) studies of the Cu 2 (Meoxpn) 2 -Gd(NO 3 ) 3 complex have revealed that the central gadolinium(III) and terminal copper(II) ions are ferromagnetically coupled with the exchange integral J (Cu-Gd)  = +3.85 cm −1 , while an antiferromagnetic coupling is detected between the two terminal copper(II) ions with the exchange integral J′ (Cu-Cu)  = −0.98 cm −1 , on the basis of the spin Hamiltonian operator [ Ĥ = −2J (Ŝ Cu1 Ŝ Gd  + Ŝ Cu2 Ŝ Gd ) − 2J′(Ŝ Cu1 Ŝ Cu2 )].