Rb2BaNb2Se11: A new quaternary niobium polyselenide with infinite anionic chains composed of Nb2Se11 building block

The 1∞[Nb2Se11]4− chain in the new mixed group1/group2 polyselenide compound Rb2BaNb2Se11 is formed by interconnection of [Nb2Se11] units via Se22− dianions. The [Nb2Se11] building blocks are formed by face sharing of two distorted pentagonal bipyramidal NbSe7 groups.