Thermodynamic Stability and Incorporation of Phosphorus into Germanium‐Doped Silica Glass

Abstract

A thermodynamic calculation of the incorporation of phosphorus into germanium‐doped silica glass is presented. The calculation predicts that, quite like germanium, the phosphorus concentration has a maximum as a function of temperature near 1800 K. In the five‐component system (CI, Ge, 0, P, Si) under typical strongly oxidizing conditions, phosphorus is lost as PO2 at equilibrium above 1800 K. A new way to minimize the Gibbs energy of the complex system is described briefly; no initial estimate of the solution components is required. This method should be widely applicable to chemical problems that involve multiple components and phases.