Atomization energies of the molecules LiSiO(g) and Si2O2(g) by mass spectrometric gaseous equilibria

Abstract

High temperature gaseous equilibria involving LiSiO(g) and Si₂O₂(g) over the mixture of Li₂O(s) and Si(s) were studied by mass spectrometry. From the measurements of the gaseous equilibria LiSiO(g)+ Li(g)= Li₂(g)+ SiO(g), Si₂O₂(g)+ Li(g)= SiO(g)+ LiSiO(g) and Si₂O₂(g)+ Li₂(g)= 2LiSiO(g), the atomization energies D^°₀(LiSiO)= 238.4 ± 5 kcal mol^–1 and D^°₀(Si₂O₂)= 442.5 ± 10 kcal mol^–1 were obtained.

The ionization potential of LiSiO(g) was determined as i.p.(LiSiO)= 6.3 ± 0.3 eV and the heats of formation were determined as: ΔH^°₀(LiSiO)=–(34.2 ± 5) kcal mol^–1 and ΔH^°₀(Si₂O₂)=–(111.2 ± 10) kcal mol^–1.