OXYFLUORINATED MICROPOROUS COMPOUNDS .8. SYNTHESIS AND STRUCTURE DETERMINATION OF V2PO8F,EN (ULM-7V) - THE 1ST OXYFLUOROVANADO(V) PHOSPHATETEMPLATED BY ETHYLENEDIAMINE

This paper describes the synthesis and the structure determination of [V2PO8F]2-, [C2N2H10]2+(en), the first oxyfluorinated vanadophosphate with an open framework structure. V2PO8F, en crystallizes in the acent ric P2(1)2(1)2(1) (No. 19) space group with cell parameters a = 8.2939 (6) angstrom, b = 9.2260(8) angstrom, c = 12.5021(8) angstrom V = 956. 7(2) angstrom3, Z = 4. The structure consists of chains of alternating VO6 octahedra and PO4 tetrahedra in the [001] direction. These chains , located at y almost-equal-to 0 and 1/2, are linked by VO5 square pyr amids at y almost-equal-to +/-1/4 levels in such a way that the two ty pes of corner-sharing vanadium polyhedra form zigzag chains along the [100] direction. This framework defines 10-membered windows in the (11 0) and (1 - 10) planes and 10-membered zigzag tunnels along [001] insi de which the diprotonated ethylenediamine is located. (C) 1994 Academi c Press, Inc.