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Stability and electronic structure of the complex K$_2$PtCl$_6$ structure-type hydrides

S. V. Halilov·D. J. Singh·M. Gupta·R. Gupta
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Abstract

The stability and bonding of the ternary complex K$_2$PtCl$_6$ structure hydrides is discussed using first principles density functional calculations. The cohesion is dominated by ionic contributions, but ligand field effects are important, and are responsible for the 18-electron rule. Similarities to oxides are discussed in terms of the electronic structure. However, phonon calculations for Sr$_2$RuH$_6$ also show differences, particularly in the polarizability of the RuH$_6$ octahedra. Nevertheless, the yet to be made compounds Pb$_2$RuH$_6$ and Be$_2$FeH$_6$ are possible ferroelectrics. The electronic structure and magnetic properties of the decomposition product, FeBe$_2$ are reported. Implications of the results for H storage are discussed.

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S. V. Halilov, D. J. Singh, M. Gupta, R. Gupta. 2004-06-22. Stability and electronic structure of the complex K$_2$PtCl$_6$ structure-type hydrides. https://doi.org/10.1103/physrevb.70.195117

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