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Very fast relaxation in polycarbonate glass

L. Saviot·E. Duval·J. F. Jal·A. J. Dianoux
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Abstract

Low-frequency Raman and inelastic neutron scattering of amorphous bis-phenol A polycarbonate is measured at low temperature, and compared. The vibrational density of states and light-vibration coupling coefficient are determined. The frequency dependences of these parameters are explained by propagating vibration modes up to an energy of about 1 meV, and fracton-like modes in more cohesive domains at higher energies. The vibrational dynamics is in agreement with a disorder in the glass, which is principally of bonding or of elasticity instead of density.

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L. Saviot, E. Duval, J. F. Jal, A. J. Dianoux. 2000-09-15. Very fast relaxation in polycarbonate glass. https://doi.org/10.1007/s100510070105

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