Piperazine templated 3D fluorogallophosphate:: synthesis and characterization of Ga5(PO4)5F4•2[N2C4H12]

A new 3D open-framework fluorogallophosphate, Ga-5(PO4)(5)F-4.2[N2C4H12], was synthesized solvothermally using either 1,4-diazabicyclo[2.2.2]octane or piperazine as a templating agent. The structure as determined from low-temperature (-105 degreesC) X-ray single crystal diffraction is orthorhombic, with space group Pccn, a = 12.232(2) Angstrom, b = 12.268(2) Angstrom, c = 16.392(3) Angstrom, V = 2460 Angstrom (3) and Z = 4. The 3D framework is built-up by corner linked PO4 tetrahedra, GaO4F trigonal bipyramids and GaO4F2 octahedra. The building block of the structure is an hexameric unit of composition 0.5 [Ga(PO4)](5)F-4. The organic template molecules reside in cavities formed by the intersection of eight member channels running along [1 0 0] and irregular pores parallel to [0 0 1]. The crystalline framework remains stable up to 350 degreesC under oxygen. (C) 2001 Elsevier Science B.V. All rights reserved.