Paper is devoted to Raman scattering study of structural transformations in frozen liquid crystal ABT in the process of its heating. Temperature region was from T=173 K up to T=343 K. A specific mechanism of inhomogeneous broadening in mesogenic systems is proposed. The mechanism consists in parametric action of valence angles deformations of molecules on high frequency vibrations. In its turn the molecular deformations depend on media structure. As a result the shape of parametrically dependent high frequency vibrational bands indirectly reacts to structural transformations in media.