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Abstract Here, the combination of theoretical computations followed by rapid experimental screening and in situ diffraction studies is demonstrated as a powerful strategy for novel compounds discovery. When applied for the previously “empty” Na−Zn−Bi system, such an approach led to four novel phases. The compositional space of this system was rapidly screened via the hydride route method and the theoretically predicted NaZnBi (PbClF type,P4/nmm) and Na11Zn2Bi5(Na11Cd2Sb5type,P) phases were successfully synthesized, while other computationally generated compounds on the list were rejected. In addition, single crystal X‐ray diffraction studies of NaZnBi indicate minor deviations from the stoichiometric 1 : 1 : 1 molar ratio. As a result, two isostructural (PbClF type,P4/nmm) Zn‐deficient phases with similar compositions, but distinctly different unit cell parameters were discovered. The vacancies on Zn sites and unit cell expansion were rationalized from bonding analysis using electronic structure calculations on stoichiometric “NaZnBi”.In‐situsynchrotron powder X‐ray diffraction studies shed light on complex equilibria in the Na−Zn−Bi system at elevated temperatures. In particular, the high‐temperature polymorphHT‐Na3Bi (BiF3type,Fmm) was obtained as a product of Na11Zn2Bi5decomposition above 611 K.HT‐Na3Bi cannot be stabilized at room temperature by quenching, and this type of structure was earlier observed in the high‐pressure polymorphHP‐Na3Bi above 0.5 GPa. The aforementioned approach of predictive synthesis can be extended to other multinary systems.
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Ternary antimonide NaCd 4 Sb 3 : hydride synthesis, crystal structure and transport properties
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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- Award ID(s):
- 1944551
- PAR ID:
- 10369809
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Zeitschrift für anorganische und allgemeine Chemie
- Volume:
- 648
- Issue:
- 15
- ISSN:
- 0044-2313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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