CRYSTAL STRUCTURE OF BETA-PLATINUM DIOXIDE

β-PtO2 crystallizes as the orthorhombic CaCl2-type structure with a = 4·488(3) A ̊, b = 4·533(3) A ̊, and c = 3·138(2) A ̊. The oxygen coordinates are found to be: x= 0·281 and y = 0·348. This leads to two long PtO bonds of 2·02 Å, four short bonds of 1·98 Å, and a mininum oxygen-oxygen approach of 2·40 Å. The Pt(IV) radius is 0·63 Å. A comparison of the PtO2 structure with the rutile form of TiO2 is presented. © 1969.