abstract
The preparation of five different compounds, [La-2(H(2)pmd)(3)(H2O)(12)] (1: ID), [La-2(H(2)pmd)(pmd)(H2O)(2)] (2: 3D), [La(H(3)pmd)(H(2)pmd)(H2O)] (3: 3D), [La-2(H(2)pmd)(3)(H2O)(2)] (4: 3D), and [La-2(H(2)pmd)(pmd)(H2O)(4)] (5: 3D), as crystalline materials from the reaction of 1,4-phenylenebis(methylene)diphosphonic acid (H(4)pmd) with lanthanum chloride is reported. Two different, fast, and economically viable synthetic approaches were employed with their various parameters being probed and, when possible, optimized to increase yields and purity: microwave-assisted synthesis (MWAS, in ca. 1 mm) and a bench procedure using standard ambient conditions (one-pot, ca. 10 min). Compounds 1 and 2 were isolated as phase pure crystalline materials. Compounds 3 and 4 were characterized by single-crystal X-ray diffraction from mixtures, and compound 5 was identified by powder X-ray diffraction studies (also from a physical mixture with 2). Structural details for all compounds were investigated by using in tandem X-ray diffraction (single-crystal and powder), electron microscopy (SEM and EDS), and FT-IR spectroscopy. Topological studies were also performed for all 3D networks. The conversion of compound 1 (ID) into 3D networks was investigated using hydrothermal, microwave, and one-pot methods: 1 was totally converted into phase-pure 2 via the hydrothermal method and one-pot method.
keywords
CRYSTAL-STRUCTURE DETERMINATION; POWDER DIFFRACTION DATA; INORGANIC 3D NETWORKS; COORDINATION POLYMERS; MICROWAVE SYNTHESIS; HYDROTHERMAL SYNTHESIS; SOLID-STATE; SOLVOTHERMAL SYNTHESIS; SELECTIVE SEPARATION; POROUS MATERIALS
subject category
Chemistry; Crystallography; Materials Science
authors
Vilela, SMF; Mendes, RF; Silva, P; Fernandes, JA; Tome, JPC; Paz, FAA
our authors
Filipe Alexandre Almeida Paz
Principal Researcher
José Alberto Pires Fernandes
Post-doc Fellowship
Ricardo Faria Mendes
Junior Researcher
Sérgio Manuel Felipe Vilela
Post-doc FellowshipProjects
acknowledgements
We would like to thank Fundacao para a Ciencia e a Tecnologia (FCT, Portugal), the European Union, QREN, FEDER, COMPETE, and Laboratorio Associado Centro de Investigacao em Materiais Ceramicos e Compositos, CICECO (PEst-C/CTM/LA0011/2011) for their general funding scheme. We further wish to thank FCT for funding the R&D project PTDC/QUI-QUI/098098/2008 (FCOMP-01-0124-FEDER-010785), and for specific funding toward the purchase of the single-crystal diffractometer. We are also grateful to FCT for the Ph.D. scholarships, Nos. SFRH/BD/46601/2008 (to P.S.) and SFRH/BD/66371/2009 (to S.M.F.V.), and the postdoctoral grant SFRH/BPD/63736/2009 (to J.A.F.).