Luminescent and magnetic cyano-bridged coordination polymers containing 4d-4f ions: toward multifunctional materials
Elena Chelebaeva1, Joulia Larionova, Yannick Guari
1Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, Chimie Moléculaire et Organisation du Solide, Université Montpellier II, Place E. Bataillon, 34095 Montpellier cedex 5, France.
Abstract:
A new family of cyano-bridged coordination polymers Ln(H(2)O)(5)[M(CN)(8)] (Ln = Eu, Tb, Sm, Gd; M = Mo, W) were obtained and characterized by X-ray diffraction, photoluminescence spectroscopy, and magnetic analyses. These compounds are isomorphous and crystallize in the tetragonal system P4/nmm, forming two-dimensional gridlike networks. The Eu- and Tb-containing coordination polymers are room-temperature optically active emitters displaying the characteristic (5)D(0) --> (7)F(0-4) (Eu(3+)) and (5)D(4) --> (7)F(6-2) (Tb(3+)) transitions. All of the coordination polymers except Eu(H(2)O)(5)[M(CN)(8)] present long-range magnetic ordering at low temperatures. The coexistence of luminescence with ferromagnetic ordering for Tb(H(2)O)(5)[M(CN)(8)] (M = Mo, W) suggests that these compounds may be considered as bifunctional magneto-luminescent coordination polymers exhibiting diverse physical responses when subjected to various external stimuli.
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