Thermal decomposition of gallium nitrate hydrate and modeling of thermolysis products

It is well established that gallium insertion into the hydroxiapatite matrix as practiced in orthopedics protects bone from resorbtion and improves the biomechanical properties of the skeletal system. The research presented in this article is an investigation into the thermal decomposition of gallium nitrate, which is part of a complex process leading to the preparation of a hybrid matrix. It was demonstrated that after melting of the hexahydrate in its own water there occurs a simultaneous condensation of 4 mol of initial monomer Ga(NO₃)₃·6H₂O into a tetramer Ga₄O₄(NO₃)₄. The resulting inorganic cycle gradually loses N₂O₅ and, through the formation of unstable oxynitrates, is transformed into gallium oxide. The use of molecular mechanics for comparing the potential energies of consecutive products of thermal decomposition permitted an evaluation of their stability and an appropriate interpretation of the experimental data.