TY - JOUR
T1 - Positional flexibility
T2 - Syntheses and characterization of six uranium chalcogenides related to the 2H hexagonal perovskite family
AU - Mesbah, Adel
AU - Prakash, Jai
AU - Beard, Jessica C.
AU - Pozzi, Eric A.
AU - Tarasenko, Mariya S.
AU - Lebègue, Sébastien
AU - Malliakas, Christos D
AU - Van Duyne, Richard P
AU - Ibers, James A
PY - 2015/3/16
Y1 - 2015/3/16
N2 - Six new uranium chalcogenides, Ba4USe6, Ba3FeUSe6, Ba3MnUSe6, Ba3MnUS6, Ba3.3Rb0.7US6, and Ba3.2K0.8US6, related to the 2H hexagonal perovskite family have been synthesized by solid-state methods at 1173 K. These isostructural compounds crystallize in the K4CdCl6 structure type in space group D3d6-R3¯c of the trigonal system with six formula units per cell. This structure type is remarkably flexible. The structures of Ba3FeUSe6, Ba3MnUSe6, and Ba3MnUS6 consist of infinite ∞1[MUQ66-] chains (M = Fe or Mn; Q = S or Se) oriented along the c axis that are separated by Ba atoms. These chains are composed of alternating M-centered octahedra and U-centered trigonal prisms sharing triangular faces; in contrast, in the structures of Ba4USe6, Ba3.3Rb0.7US6, and Ba3.2K0.8US6, there are U-centered octahedra alternating with Ba-, Rb-, or K-centered trigonal prisms. Moreover, the Ba4USe6, Ba3FeUSe6, Ba3MnUSe6, and Ba3MnUS6 compounds contain U4+, whereas Ba3.3Rb0.7US6 and Ba3.2K0.8US6 are mixed U4+/5+ compounds. Resistivity and μ-Raman spectroscopic measurements and DFT calculations provide additional insight into these interesting subtle structural variations.
AB - Six new uranium chalcogenides, Ba4USe6, Ba3FeUSe6, Ba3MnUSe6, Ba3MnUS6, Ba3.3Rb0.7US6, and Ba3.2K0.8US6, related to the 2H hexagonal perovskite family have been synthesized by solid-state methods at 1173 K. These isostructural compounds crystallize in the K4CdCl6 structure type in space group D3d6-R3¯c of the trigonal system with six formula units per cell. This structure type is remarkably flexible. The structures of Ba3FeUSe6, Ba3MnUSe6, and Ba3MnUS6 consist of infinite ∞1[MUQ66-] chains (M = Fe or Mn; Q = S or Se) oriented along the c axis that are separated by Ba atoms. These chains are composed of alternating M-centered octahedra and U-centered trigonal prisms sharing triangular faces; in contrast, in the structures of Ba4USe6, Ba3.3Rb0.7US6, and Ba3.2K0.8US6, there are U-centered octahedra alternating with Ba-, Rb-, or K-centered trigonal prisms. Moreover, the Ba4USe6, Ba3FeUSe6, Ba3MnUSe6, and Ba3MnUS6 compounds contain U4+, whereas Ba3.3Rb0.7US6 and Ba3.2K0.8US6 are mixed U4+/5+ compounds. Resistivity and μ-Raman spectroscopic measurements and DFT calculations provide additional insight into these interesting subtle structural variations.
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U2 - 10.1021/ic5029806
DO - 10.1021/ic5029806
M3 - Article
C2 - 25697078
AN - SCOPUS:84924943969
VL - 54
SP - 2851
EP - 2857
JO - Inorganic Chemistry
JF - Inorganic Chemistry
SN - 0020-1669
IS - 6
ER -