Showing papers by "Guillermo Mínguez Espallargas published in 2012"
TL;DR: It is shown that the chemisorption of gaseous HCl molecules by a non-porous one-dimensional coordination polymer instigates drastic modifications in the magnetic properties of the material.
Abstract: Tuning the properties of responsive materials by applying an external stimulus could lead to their application as chemical switches or molecular sensors. Coronado et al. develop a non-porous one-dimensional coordination polymer, the magnetic properties of which undergo drastic changes on chemisorption of gaseous HCl.
94 citations
TL;DR: Two families of coordination polymers, {[M(btix)(2)(OH(2))(2)]·2NO(3)·2H(2)O}(n) [M = Co (1), Zn (2), Co-Zn (3)], have been synthesized and characterized.
Abstract: Two families of coordination polymers, {[M(btix)2(OH2)2]·2NO3·2H2O}n [M = Co (1), Zn (2), Co–Zn (3); btix = 1,4-bis(triazol-1-ylmethyl)benzene] and {[M(btix)2(NO3)2]}n [M = Co (4), Zn (5), Co–Zn (6)], have been synthesized and characterized. The two conformations of the ligand, syn and anti, lead to one-dimensional (1D) cationic chains or two-dimensional (2D) neutral grids. Extrusion of the water molecules of the 1D compounds results in an irreversible transformation into the 2D compounds, which involves a change in conformation of the btix ligands and a rearrangement in the metal environment with cleavage and reformation of covalent bonds. This structural transformation has been followed by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements to monitor the minor modifications that the metal centers suffer.
35 citations
TL;DR: Halogen bonds have been applied for the supramolecular organization of organic free radicals in the solid state and their role in the propagation of the magnetic exchange has been studied in this article.
Abstract: Halogen bonds have been applied for the supramolecular organization of organic free radicals in the solid state and their role in the propagation of the magnetic exchange has been studied.
28 citations
TL;DR: Interestingly, an irreversible exchange occurs with N(3)(-) anions to generate a new coordination polymer, [Cu(btix)(N(3))(2)](n), whose structure has been determined ab initio by powder X-ray diffraction, revealing a totally different connectivity between the Cu(II) centers.
Abstract: A three-dimensional coordination polymer, [Cu(btix)2(BF4)2]n [btix = 1,4-bis(triazol-1-ylmethyl)benzene], with antiferromagnetic interactions occurring via the organic ligand, has been prepared and characterized. It has been shown to permit the exchange of anionic species in the crystalline network with modification of the magnetic properties. Coordinated BF4– can be reversibly exchanged by different anions with (NO3– and Cl–) or without (PF6– and ClO4–) dynamic response of the organic ligand, which acts as the only linker between the metal centers. Interestingly, an irreversible exchange occurs with N3– anions to generate a new coordination polymer, [Cu(btix)(N3)2]n, whose structure has been determined ab initio by powder X-ray diffraction, revealing a totally different connectivity between the CuII centers. These structural transformations are accompanied by a change of the magnetic properties, which have been detected by electron paramagnetic resonance and magnetic susceptibility measurements.
23 citations