Doubly bridged molecular ribbons in the structure of an ionic complex, hydronium zinc(II) pyrazine-2,3-dicarboxylate

The structure of dihydronium [ catena -bis(µ-pyrazine-2,3-dicarboxylato-N,O,O')zinc(II)], (H3O)2[Zn(2,3PZDC)2], is composed of polyanionic ribbons of zinc(II) ions linked by double bridging 2,3-PZDC ligand molecules. Each ligand uses an N,O bonding moiety formed by one carboxylic group [Zn–O 2.071(2)?Å; Zn–N 2.184(2)?Å] and a monodentate oxygen atom of the other carboxylate group [Zn–O 2.092(2)?Å]. Coordination around the zinc(II) ion is strongly distorted octahedral. Hydronium cations (H3O) 1+ link the ribbons by hydrogen bonds.