Design of lanthanide metal organic frameworks incorporating dicarboxylate ligands

International audienc

Structural and Magnetocaloric Properties of ErFe 2 . 4 Al 0 . 6 Compound

International audienc

Synthesis and Crystal Structures of Various Phases of the Microporous Three-Dimensional Coordination Polymer [Zr(OH)₂(C₂O₄)]_<i>n</i>

A homometallic Zr­(IV)-oxalate three-dimensional (3-D) coordination polymer of formula [Zr­(OH)₂(C₂O₄)­·0.5H₂O] is reported. This compound was found to be a microporous solid with reversible sorption abilities. Upon guest release and sorption, the crystalline material undergoes single crystal to single crystal transitions. The crystal structures for three phases have been solved from single crystal diffraction studies. They consist of the guest containing frameworks [Zr­(OH)₂(C₂O₄)­·0.5H₂O], <b>1</b>,<b> 3</b>, and the guest-free porous phase [Zr­(OH)₂(C₂O₄)], <b>2</b>; all are found with tetragonal space group <i>I</i>4/<i>m</i>. Phase <b>1</b> has been obtained by controlled diffusion of the reagents (ZrO­(NO₃)₂ and H₂C₂O₄) in a silica gel medium; the other phases have been formed from <b>1</b> by thermal activation (<b>2</b>) and re-adsorption of H₂O (<b>3</b>)

Synthesis and Crystal Structures of Various Phases of the Microporous Three-Dimensional Coordination Polymer [Zr(OH)₂(C₂O₄)]_<i>n</i>

A homometallic Zr­(IV)-oxalate three-dimensional (3-D) coordination polymer of formula [Zr­(OH)₂(C₂O₄)­·0.5H₂O] is reported. This compound was found to be a microporous solid with reversible sorption abilities. Upon guest release and sorption, the crystalline material undergoes single crystal to single crystal transitions. The crystal structures for three phases have been solved from single crystal diffraction studies. They consist of the guest containing frameworks [Zr­(OH)₂(C₂O₄)­·0.5H₂O], <b>1</b>,<b> 3</b>, and the guest-free porous phase [Zr­(OH)₂(C₂O₄)], <b>2</b>; all are found with tetragonal space group <i>I</i>4/<i>m</i>. Phase <b>1</b> has been obtained by controlled diffusion of the reagents (ZrO­(NO₃)₂ and H₂C₂O₄) in a silica gel medium; the other phases have been formed from <b>1</b> by thermal activation (<b>2</b>) and re-adsorption of H₂O (<b>3</b>)

The solid solution (Fe0.81Al0.19)(H2PO4)3 with a strong hydrogen bond

A sample of synthetic (Fe0.81Al0.19)(H2PO4)3 was prepared by hydro­thermal methods in order to determine the crystal structure. The compound is a new monoclinic variety (γ-form) and the structure is based on a two-dimensional framework of distorted corner-sharing MO6 (M = Fe, Al) polyhedra sharing corners with PO4 tetra­hedra