We report a highly efficient charge separation system, D-Pt-A, where D (triphenylamine) and A (naphthatenediimide) are bonded to the Pt moiety through highly twisted phenylene ethynylene linkages. The quantum yields for the formation of the charge-separated state were determined to be nearly unity. The lifetimes of D+-Pt-A(-) were similar to 1 mu s at room temperature and much longer at low temperature. The spin-correlated radical ion pair was directly observed by means of time-resolved EPR spectroscopy.