The anharmonic character of T-g and T-m transition

The idea of anharmonic oscillations has been extended to explain the glass transition or melting point. All ideas of free volume, vacancy transport, e tc., have been respected but are treated as minor phenomena relative to har monic-anharmonic vibration transition. A simple model of coupled oscillator s is studied, it is shown that coupled anharmonic oscillators can produce v ibrations on entirely different levels of amplitudes, which explains the hi ghly different coefficients of thermal expansion and c(p) values for solid and liquid states. At higher temperatures, for polymers in the rubber-like zone, the theory of anharmonic coupled oscillators brings certain justifica tion for the theories of De Gennes, Doi and Edwards or Rouse. The solid-liq uid transition seems to be connected on microlevel mainly with the enlargem ent of vibrational amplitudes of monomer or dimer units in polymer chain as the temperature increases.