The shape of vibrational lines and the temperature dependences of their width for structures with short-range and medium-range orders in oxide glasses have been studied.The relationship describing the contour of the line associated with internal vibrations of glass-forming polyhedra is derived in the framework of the model for deformation broadening of the vibrational spectra of two-level systems.It is found that the line within the width is represented by a Lorentzian contour,and the line wings decay as (#omega#-#omega#_0)~(-4).It is demonstrated that a similar contour is observed for the lines corrwesponding to the intrinsic vibrations of clusters with hingedbonds,which form the boson peak.The shape of teh line at 806 cm~(-1) for vitreous boron oxide,which is calculated in the framework of the propsed model,is in complete agreement with the experimental data in the temperature range 80-1900 K.
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