Zeolite Pb,Br,H,Cs,Na-Y was prepared by the reaction of Cs 49 Na 22 -Y with PbBr 2 in a mixed organic solvent, and the structure of a single crystal of it was determined crystallographically. About 26% of its supercages hold a tetrahedral PbBr 42− ion at their centers. Each is surrounded by six Cs + ions, each of which bridges between the two Br − ions on each edge of the PbBr 4 2− tetrahedron. Each of these four Br − ions also bonds to a Na + ion near the center of a 6-ring. The result is a Na 4 Cs 6 PbBr 4 8+ quantum dot (QD) of symmetry 4̅ 3m (T d ). The supercage in this zeolite (Si/Al = 1.69) has an average charge of 8.9−, which nearly balances the 8+ charge of this QD. Water molecules in 12-rings bridge (Cs + −H 2 O−Cs + ) between QDs in adjacent supercages to form domains of tetrahedrally arranged QDs. Both these QDs and these domains are seen directly by electron microscopy. These QDs, when excited by UV radiation, luminesce sharply at 528 nm (green, FWHM = 17.8 nm). Pb,Br,H,Cs,Na-Y and its luminescence are entirely stable in the atmosphere; the bridging water molecules enhance the luminescence and provide that stability. Structure refinement was done in the space group Fd3̅ m (a = 24.889(4) Å) with the 886 unique reflections for which F o > 3σ(F o ) to the final error index R 1 = 0.077. Its composition was confirmed by energy dispersive X-ray analysis.

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Partially hydrated zeolite Cs,Na−Y (|Cs 51 Na 24 | [Si 117 Al 75 O 384 ]-FAU) was allowed to react with SnI 2 . The crystal structures of fully dehydrated Cs,Na−Y and of the partially hydrated product Sn,I,Cs,Na−Y (|(Na 4 Cs 6 Sn 4 I 6 ) 0.625 Cs 46 Na 21.5 (H 2 O) 26 | [Si 117 Al 75 O 384 ]-FAU) were determined by single-crystal crystallography using synchrotron X-radiation. They were refined in the space group Fd3m, (a = 24.838(2) Å and 24.873(2) Å) with all unique data to the final error indexes R 1 = 0.053 and 0.060 for the 1885 and 1400 reflections for which F o > 4σ(F o ), respectively. Tetrahedrally distorted Sn 4 I 44+ cubes, symmetry 43m (T d ), center 7.9% of the supercages in the zeolite crystal studied. Each is supported there by four Na + ions and six Cs + ions that bridge between its I − ions and oxygen atoms of the zeolite framework. Each Sn 2+ ion bonds to an additional I − ion in the plane of a 12-ring, which in turn bonds to a Sn 2+ ion in a Sn 4 I 4 4+ group in a neighboring supercage. In this way, the Sn 4 I 4 4+ units connect to form a three-dimensional continuum with formula Na 4 Cs 6 Sn 4 I 6 12+ per supercage. Partially hydrated zeolite Sn,I,Cs,Na−Y has a broad luminescence range from 400 to 800 nm. Upon further hydration, the luminescence spectrum evolved, and its color changed from pale yellow to white.

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