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- National Science Foundation
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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.more »
Crystal Growth of New Germanate Framework Structures: Impact of the Presence of Square Planar Copper Species and Mixed Ge/Mn Sites on the Overall Structures of Rb 2 Cu 3 Ge 5 O 14 , Cs 2 Cu 3 Ge 5 O 14 , Cs 7 Cu 2 Ge 11 O 27 F, and [(Cs 6 F)(Cs 3 AgF)][Ge 12 Mn 2 O 32 ]
The crystal structure, electron energy-loss spectroscopy (EELS), heat capacity, and anisotropic magnetic and resistivity measurements are reported for Sn flux grown single crystals of orthorhombic Pr2Co3Ge5(U2Co3Si5-type,
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