ScPdZn and ScPtZn with YAlGe type structure: group-subgroup relation and 45Sc solid state NMR spectroscopy
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
04/06/2014
04/06/2014
01/02/2013
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Resumo |
The intermetallic compounds ScPdZn and ScPtZn were prepared from the elements by high-frequency melting in sealed tantalum ampoules. Both structures were refined from single crystal X-ray diffractometer data: YAlGe type, Cmcm, a = 429.53(8), b = 907.7(1), c = 527.86(1) pm, wR2 = 0.0375, 231 F2 values, for ScPdZn and a = 425.3(1), b = 918.4(2), c = 523.3(1) pm, wR2 = 0.0399, 213 F2 values for ScPtZn with 14 variables per refinement. The structures are orthorhombically distorted variants of the AlB2 type. The scandium and palladium (platinum atoms) build up ordered networks Sc3Pd3 and Sc3Pt3 (boron networks) which are slightly shifted with respect to each other. These networks are penetrated by chains of zinc atoms (262 pm in ScPtZn) which correspond to the aluminum positions, i.e. Zn(ScPd) and Zn(ScPt). The corresponding group-subgroup scheme and the differences in chemical bonding with respect to other AlB2-derived REPdZn and REPtZn compounds are discussed. 45Sc solid state NMR spectra confirm the single crystallographic scandium sites. From electronic band structure calculations the two compounds are found metallic with free electron like behavior at the Fermi level. A larger cohesive energy for ScPtZn suggests a more strongly bonded intermetallic than ScPdZn. Electron localization and overlap population analyses identify the largest bonding for scandium with the transition metal (Pd, Pt). DFG NRW Forschungsschule Molecules and Materials |
Identificador |
Zeitschrift für Anorganische und Allgemeine Chemie, Weinheim : Wiley - VCH Verlag, v. 639, n. 2, p. 246-253, Feb. 2013 0044-2313 http://www.producao.usp.br/handle/BDPI/45269 10.1002/zaac.201200200 |
Idioma(s) |
eng |
Publicador |
Wiley - VCH Verlag Weinheim |
Relação |
Journal of Inorganic and General Chemistry / Zeitschrift für Anorganische und Allgemeine Chemie |
Direitos |
restrictedAccess Copyright WILEY-VCH Verlag GmbH & Co. KGaA |
Palavras-Chave | #Scandium #Superstructure #Group-subgroup relation #Electronic structure #ESPECTROSCOPIA DE RESSONÂNCIA MAGNÉTICA NUCLEAR #DIFRAÇÃO POR RAIOS X |
Tipo |
article original article publishedVersion |