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Abstract A new compound NaCd4Sb3(Rm,a=4.7013(1) Å,c=35.325(1), Å, Z=3,T=100 K) featuring the RbCd4As3structure type has been discovered in the Na−Cd−Sb system, in addition to the previously reported NaCdSb phase. NaCd4Sb3and NaCdSb were herein synthesized using sodium hydride as the source of sodium. The hydride method allows for targeted sample composition, improved precursor mixing, and an overall quicker synthesis time when compared to traditional methods using Na metal as a precursor. The NaCd4Sb3structure was determined from single‐crystal X‐ray diffraction and contained the splitting of a Cd site not seen in previous isostructural phases. NaCd4Sb3decomposes into NaCdSb plus melt at 766 K, as determined viain‐situhigh‐temperature PXRD. The electronic structure calculations predict the NaCd4Sb3phase to be semi‐metallic, which compliments the measured thermoelectric property data, indicative of ap‐type semi‐metallic material. The crystal structure, elemental analysis, thermal properties, and electronic structure are herein discussed in further detail.
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Experimental and Theoretical Study on the Substitution Patterns in Lithium Germanides: The Case of Li 15 Ge 4 vs Li 14 ZnGe 4
Abstract A new ternary lithium zinc germanide, Li13.83Zn1.17(2)Ge4, was synthesized by a high‐temperature solid state reaction of the respective elements. The crystal structure was determined by single‐crystal X‐ray diffraction methods. The new phase crystallizes in the body‐centered cubic space groupI3d(no. 220) with unit cell parameter of 10.695(1) Å. The crystal structure refinements show that the parent Li15Ge4structure is stabilized as Li15−xZnxGe4(x≈1) via random substitution of Li atoms by the one‐electron‐richer atoms of the element Zn, by virtue of which the number of valence electrons increases, leading to a more electronically stable system. The substitution effects in the parent Li15Ge4structure were investigated through both theory and experiment, which confirm that the Zn atoms in this structure prefer to occupy only one of the two available crystallographic sites for Li. The preferred substitution pattern established from experimental results is supported by DFT electronic structure calculations, which also explore the subtleties of the chemical bonding and the electronic properties of the title compounds.
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- Award ID(s):
- 2004579
- PAR ID:
- 10362440
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- European Journal of Inorganic Chemistry
- Volume:
- 2022
- Issue:
- 4
- ISSN:
- 1434-1948
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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