About the Chemistry of Phosphorus Suboxides The authors thank J. Clade, A. Tellenbach, and M. Jansen (Max-Planck-Institut, Stuttgart) for many fruitful discussions. This work was supported by the Deutsche Forschungsgesellschaft (Sonderforschungsbereich 334) and the Fonds der Chemischen Industrie. Service and computer time from the HRLZ Jülich were essential for the present study.