Electronic and molecular structure of 2,2'-bipyrimidine-bridged bis(organoplatinum) complexes in various oxidation states. Radical-bridged diplatinum species and the absence of a Pt(III)/Pt(II) mixed-valent intermediate. Inorganica Chimica Acta, (264)1-2:269--278, 1997. [PUMA: bipyrimidine bridged crystal dinuclear;electrochem dinuclear;electronic diplatinum;DFT mol organoplatinum oxidn platinum structure]