A zirconium-containing sandwich-type dimer based on trivacant α- and β-[GeW9O34]10− units, [Zr3O(OH)2(α-GeW9O34)(β-GeW9O34)]12−

A new zirconium-containing sandwich-type dimer based on trivacant α- and β-[GeW9O34]10− units, [Zr3O(OH)2(α-GeW9O34)(β-GeW9O34)]12−, was synthesized and characterized by IR spectroscopy, UV electronic spectroscopy and single crystal X-ray diffraction. The central bent of the polyanion contains three oxygen atoms alternating with the three zirconium atoms. The polyanion represents a rare example of the sandwich POMs containing two different isomer subunits.