A nanoporous zinc gallophosphate framework, NTHU-4, possessing 14-ring channels, disordered rims, and two luminant analogues, NTHU-4Y and NTHU-4W, has been synthesized and characterized; NTHU-4Y is an intrinsic yellow phosphor, while NTHU-4W is a white phosphor. The unique tetrahedral framework can be excited by wavelengths longer than 254 nm to give intense yellow-to-white luminescence. Subtle changes in disorderliness were observed to be related to the distinct photoluminescence property.

Four new rare earth gallosilicates, Rb 2REGaSi4O12 (RE = Y, Eu, Gd, and Tb, denoted as REGS-1), have been synthesized under high-temperature, high-pressure hydrothermal conditions and characterized by single-crystal X-ray diffraction. They are the first examples of rare earth gallosilicates that contain individually occupied tetrahedral Ga(3+) and Si(4+) centers. The unique structure is formed of two 1D and one 2D substructural units: unbranched achter single chains which are seldom observed in silicates, the PaCl 5-type infinite chains formed of edge-sharing REO7 petagonal bipyramids and the unprecedented mixed-anion double layers with the composition [GaSi4O12]. The photoluminescence properties of EuGS-1 and TbGS-1 have been studied. The Y(3+) ion in YGS-1 can be partially replaced by Eu(3+) and Tb(3+) to yield luminescent materials.

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