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Cohesion of BaReH$_9$ and BaMnH$_9$: Density Functional Calculations and Prediction of (MnH$_9)^{2-}$ Salts

D. J. Singh·M. Gupta·R. Gupta
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Abstract

Density functional calculations are used to calculate the structural and electronic properties of BaReH$_9$ and to analyze the bonding in this compound. The high coordination in BaReH$_9$ is due to bonding between Re 5$d$ states and states of $d$-like symmetry formed from combinations of H $s$ orbitals in the H$_9$ cage. This explains the structure of the material, its short bond lengths and other physical properties, such as the high band gap. We compare with results for hypothetical BaMnH$_9$, which we find to have similar bonding and cohesion to the Re compound. This suggests that it may be possible to synthesize (MnH$_9)^{2-}$ salts. Depending on the particular cation, such salts may have exceptionally high hydrogen contents, in excess of 10 weight %

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D. J. Singh, M. Gupta, R. Gupta. 2006-08-30. Cohesion of BaReH$_9$ and BaMnH$_9$: Density Functional Calculations and Prediction of (MnH$_9)^{2-}$ Salts. https://doi.org/10.1103/physrevb.75.035103

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