STANDARD GIBBS ENERGIES OF FORMATION OF SICL2(G) AND SICL3(G) SPECIESAT 1000-K TO 1300-K

The equilibria in the Si(s)-Cl-2(g) system have been studied at temper ature from 1000 to 1300 K using a transpiration reactor. The equilibri a are considered among Si(s)-Cl-2(g)-SiCl2 (g)-SiCl3(g)-SiCl4(g). The standard Gibbs energies of formation for the species of SiCl2(g) and S iCl3(g) species at these temperatures are determined simultaneously, w here these subchloride species coexist in appreciable quantities with SiCl4 in the gas phase at these temperatures, as follows: SiCl2(g): De lta(f-SiCl2-T)degrees(1000-1300 K)=-185.0-2.32 x 10(-2) T kJ . mol(-1) SiCl3(g): Delta(f-SiCl3-T)degrees(1000-1300 K)=-401.1+3.28 x 10(-2) T kJ . mol(-1).