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  1. Mild hydrothermal synthesis was employed to grow high-quality single crystals of ternary fluoridohafnates at low temperatures. The series of new materials was characterized using single crystal X-ray diffraction, and the crystal structures for AHfF6 (A= Mg and Sr), A2HfF8 (A= Ba and Pb), Ca5Hf3F22 and Cd2HfF8(H2O)6 are discussed herein. Although some material compositions have similar stoichiometries, all the compositions adopt different structural motifs. A comparison of the crystal structures and synthesis techniques of ternary fluoridohafnates and ternary fluoridozirconates is also reported, and the impact of the subtle changes of synthesis conditions on overall structures is discussed. 
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    Free, publicly-accessible full text available July 31, 2024
  2. null (Ed.)
    A series of new Ce( iv ) based fluorides with two different compositions, Cs 2 MCe 3 F 16 (M = Ni 2+ , Co 2+ , Mn 2+ , and Zn 2+ ) and Na 3 MCe 6 F 30 (M = Al 3+ , Ga 3+ , Fe 3+ , and Cr 3+ ) were synthesized as high quality single crystals via a mild hydrothermal route. The compounds with the composition Cs 2 MCe 3 F 16 (M = Ni 2+ , Co 2+ , Mn 2+ , and Zn 2+ ) crystallize in the hexagonal crystal system with space group P 6 3 / mmc and are isotypic with the uranium analogs, whereas the Na 3 MCe 6 F 30 (M = Al 3+ , Ga 3+ , Fe 3+ , and Cr 3+ ) compounds crystallize in the trigonal space group P 3̄ c 1 and are isotypic with the uranium and thorium analogs Na x MM′ 6 F 30 (M′ = Th, U). The Cs 2 MCe 3 F 16 compounds exhibit a complex 3D crystal structure constructed of edge-sharing cerium trimers, in which all three Ce atoms share a common μ 3 -F unit. The Na 3 MCe 6 F 30 compounds are constructed of edge- and vertex-sharing cerium polyhedra connected to each other to form Ce 6 F 30 6− framework, which can accommodate only relatively smaller trivalent cations (M 3+ = Al 3+ , Ga 3+ , Fe 3+ , and Cr 3+ ) as compared to uranium and thorium analogs. Magnetic susceptibility measurements were carried out on the samples of Cs 2 MCe 3 F 16 (M = Ni 2+ and Co 2+ ), which exhibit paramagnetic behavior. 
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  3. null (Ed.)
    A new self-activated X-ray scintillator, BaWO 2 F 4 , with an excellent photoluminescence quantum efficiency is reported. Hydrothermally grown single crystals, space group P 2/ n , exhibit a 3D framework structure containing isolated WO 2 F 4 octahedra. BaWO 2 F 4 exhibits green emission under UV light with a high quantum yield of 53% and scintillates when exposed to X-rays(Cu). 
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