Undecahydrohexaborate anion
= Undecahydrohexaborate anion
{title2=$[\mathrm{B_6H_{11}}]^-$}
$[\mathrm{B_6H_{11}}]^-$, an <arachno> <borane> anion with nine skeletal pairs. A localized BH3-adduct drawing does not describe its lowest-energy fluxional cage adequately.