title: Framework solids based on copper(II) halides (Cl/Br) and methylene-bridged bis(1-hydroxybenzotriazole): synthesis, crystal structures, magneto-structural correlation, and density functional theory (DFT) studies.
abstract: A methylene-bridged 1-hydroxybenzotriazole derived ligand L [L = 1, 3-bis(benzotriazol-1-yl)-1,3-dioxapropane] has been synthesized and characterized by spectroscopic and structural methods. Reaction of L with two different copper(II) halides [CuX(2); X = Br, Cl] in an identical condition yields two different compounds of similar compositions, {[Cu(μ-Br)(Br)(μ-L)](2)}(n)·2nH(2)O (1) and {[Cu(μ-Cl)(Cl)(μ-L)](2)}(n)·2nH(2)O (2), both being characterized by various physicochemical techniques. Single crystal X-ray studies reveal that they appear as 2D coordination polymers with similar bridging fashion of L. Low temperature magnetic susceptibility measurements reveal antiferromagnetic and ferromagnetic behaviors for 1 and 2 with magnetic coupling constants J = -15.2 and +1.7 cm(-1), which are in a reasonable agreement with their calculated values (J = -9.79 and +0.68 cm(-1) respectively, for 1 and 2). The role of bridging halides in the structure and magnetic properties of the complexes are investigated, and a possible magneto-structural correlation has been established. Influence of spin density of bridging halides on the magnitude of coupling constants has been discussed with the help of density functional theory (DFT) calculations.
authors.affiliation: Department of Chemistry, Jadavpur University, Raja S. C. Mullik Road, Kolkata-700 032, West Bengal, India.
authors.forename: Ashok
authors.initials: A
authors.lastname: Sasmal
authors.forename: Shyamapada
authors.initials: S
authors.lastname: Shit
authors.forename: Corrado
authors.initials: C
authors.lastname: Rizzoli
authors.forename: Hongfeng
authors.initials: H
authors.lastname: Wang
authors.forename: Cédric
authors.initials: C
authors.lastname: Desplanches
authors.forename: Samiran
authors.initials: S
authors.lastname: Mitra