This paper describes the calculation of unimolecular dissociation of SF6, SF5, SF4, SF3, SF2 in temperature range T ∈ (500,6000) K at the low pressure limit. The theory is based on the
solution of the master equation. The strong collision assumption is used. The basic simplified
expression for harmonic oscillator model is improved by factors of anharmonicity, energy
dependence of the density of states and external and internal rotations.