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Hydride ion, as I know is a pretty powerful base, much stronger than hydroxide ion and cannot exist in an aqueous phase.

Can it act as a ligand in coordination compounds? Hydride ion has its electronic configuration as $\mathrm{1s^2}$ in a symmetrical s orbital so the tendency to donate a lone pair into a metal atom would be less. But can its high nucleophilicity allow it to bind to the metal atom despite the symmetry of its orbital?

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Yes, there are many examples. For instance

A quick google also shows up http://www.ilpi.com/organomet/hydride.html

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    $\begingroup$ Are these coordination compounds? I thought in LiAlH4 and others, the hydrogen was covalently bonded with the metal atom. Is it a dative bond that exists between them? $\endgroup$ – Pritt says Reinstate Monica Apr 20 '17 at 7:47
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    $\begingroup$ Does the model of the bonding matter? In $\ce{MnF6^{2-}}$ the best model is probably ionic while in $\ce{PtI6^{2-}}$ covalent is probably nearer to the truth, and then you have $\ce{{Cu(NH3)_4}^{2+}}$ where some kind of dative bond is the most intuitive model. But I think we'd all be happy to call them metal complexes, which are examples of coordination compounds. $\endgroup$ – Ian Bush Apr 20 '17 at 8:07
  • $\begingroup$ I guess thats true $\endgroup$ – Pritt says Reinstate Monica Apr 20 '17 at 8:46
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    $\begingroup$ There’s also the nice case of pentacarbonyl iron which, when hydroxide ions are added, reacts to give $\ce{[Fe(CO)4(COOH)]-}$ which then rearranges and liberates $\ce{CO2}$ to give $\ce{[FeH(CO)4]-}$. This compound is Brønsted amphotheric: it can be protonated to give neutral $\ce{[FeH2(CO4)]}$ or deprotonated to give $\ce{[Fe(CO)4]^2-}$. I think it’s fascinating! $\endgroup$ – Jan Jun 18 '17 at 17:25

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