Structure Cristalline de KYP2O7

Kyp4o12

“…This type of isolation appears responsible for the good fluorescence properties shown in lanthanide compounds, such as those of the series MINdP4Ot2 (M I = Li, Na and K) (Otsuka, Miyazawa, Yamada, Iwasaki & Nakano, 1977;Chinn & Hong, 1975;Tsujimoto, Fukuda & Fukai, 1977;Tofield, Weber, Damen & Liao, 1975 (Koizumi, 1976b) and RbNdP4Ot2 (6.129 ,/k). The structures of KYP207 (Hamady, Zid & Jouini, 1994) and the related compound RbYP207 (Akrim, Zambon, Metin & Cousseins, 1993) Abstract Potassium yttrium cyclotetraphosphate is isostructural with RbNdP4012. The structure is built up from P4OI~-cyclotetraphosphate anions linked by YO8 polyhedra to form a three-dimensional framework, which delimits intersecting tunnels in which the K + ions are located.…”

NaYP2O7

“…The fourth type is only represented by a-NaTiP207 (Leclaire, Benmoussa, Borel, Grandin & Raveau, 1988). A fifth type occurs for the KYP207 structure which we have reported recently (Hamady, Zid & Jouini, 1994). The diphosphates of rare earth metals and yttrium, obtained with an alkali metal larger than K, belong to structural type I (Gabrlica-Robert & Tarte, 1982).…”

“…show a nearly staggered configuration intermediate between that in KYP207 [Hamady, Zid & Jouini (1994). J.…”

Phase equilibria in the ErPO4–KPO3 system

“…For the last few decades, double diphosphates of a general formula M I LnP 2 O 7 (M I = Li, Na, K, Rb, Cs, Tl, Ag; M III = Al, Ga, In, Fe, Sc, Y, Ln, transition metal) have attracted considerable interest [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. It has been primarily focused on the crystal structure, synthesis methods and prospective practical applications.…”

“…2. Stoichiometric amounts of substrate phosphates LnPO 4 and M I PO 3 ; the synthesis was carried out in the temperature range 400-900°C [5][6][7][8] 4 ; the synthesis proceeded in the temperature range 400-1200°C [9][10][11][12][13][14][15][16][17][18].…”