QUATERNARY SELENIDOGERMANATES(IV) A(3)[AGGE4SE10]CENTER-DOT-2H(2)O AND A(2)[MNGE4SE10]CENTER-DOT-3H(2)O (A=RB, CS) WITH OPEN FRAMEWORK STRUCTURES

Hydrothermal reaction of Ge and Se with Ag(CH3COO) in the presence of alkali metal carbonates affords the open framework selenidogermanates( IV) A(3)[AgGe4Se10]. 2H(2)O (A = Rb, Cs), 1 and 2, which contain corne r linked adamantane-like Ce4Se10 cages and AgSe4 tetrahedra. The analo gous reaction with Mn(CH3COO)(2) yields the isostructural tetragonal c ompounds A(2)[MnGe4Se10]. 3H(2)O (A = Rb, Cs), 3 and 4. The cations ar e sited at a general position in the channels of the silver bridged an ionic framework of 1 and 2 and exhibit a disordered pattern of occupat ion (s.o.f. = 0.75) with one of the two crystallographically independe nt water oxygen atoms O(2) (s.o.f. = 0.25). In contrast, the Rb+ catio ns in 3 are disordered over all three cation/oxygen sites, and the cat ion/water occupation pattern is fully reversed for the larger Cs+ cati ons in 4 in comparison to 1 and 2.