The pyrolysis of disilane and rate constants of silene insertion reactions

The pyrolysis of disilane has been studied over the range of conditions, 23 to 100 Torr (3.1 to 13.3 kN m-2) initial pressure and 283 to 340 °C. Copyrolyses with each of the four methylated monosilanes have also been conducted. The experimental evidence establishes the pyrolysis mechanism as proceeding via initial decomposition to silene (SiH2) and monosilane followed by silene insertion into disilane. Secondary insertion processes lead to formation of tetrasilanes and, later in the reaction, a polymer of composition (SiH2)n is formed. This polymer breaks down to yield hydrogen and, ultimately, silicon.