abstract
A new family of mixed-lanthanide cyano-bridged coordination polymers Ln(0.5)Ln(0.5)'(H2O)(5)[W(CN)(8)] (where Ln/Ln' = Eu3+/Tb3+, Eu3+/Gd3+, and Tb3+/Sm3+) containing two lanthanide and one transition metal ions were obtained and characterized by X-ray diffraction, photoluminescence spectroscopy, magnetic analyses, and theoretical computation. These compounds are isotypical and crystallize in the tetragonal system P4/nmm forming two-dimensional grid-like networks. They present a magnetic ordering at low temperature and display the red Eu3+ (D-5(0) -> F-7(0-4)) and green Tb3+ (D-5(4) -> F-7(6-2)) characteristic photoluminescence. The Tb0.5Eu0.5(H2O)(5)[W(CN)(8)] compound presents therefore green and red emission and shows Tb3+-to-Eu3+ energy transfer.
keywords
AUGMENTED-WAVE METHOD; MAGNETIC-PROPERTIES; MULTIFUNCTIONAL MATERIALS; ENERGY-TRANSFER; IONS; CRYSTAL; MOLECULE; LUMINESCENT; COMPLEXES; NETWORKS
subject category
Chemistry
authors
Chelebaeva, E; Long, J; Larionova, J; Ferreira, RAS; Carlos, LD; Paz, FAA; Gomes, JBR; Trifonov, A; Guerin, C; Guari, Y
our authors
Filipe Alexandre Almeida Paz
Principal Researcher
Luís Carlos
Full professor
Maria Rute de Amorim e Sá Ferreira André
Full professoracknowledgements
The authors thank Mme. Corine Rebeil (UM2, Institute Charles Gerhardt Montpellier, France) for magnetic measurements. The authors are grateful to Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) for the financial support toward the purchase of the single-crystal diffractometer and funding (PPCDT/QUI/58377/2004 and PDTC/QUI-QUI/098098/2008). The authors also wish to thank CRUP-PAUILF (Portugal-France bilateral program), CNRS, the Universite Montpellier II.