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Session 120 - The Local Interstellar Medium.
Oral session, Thursday, January 18
Corte Real, Hilton

[120.06] New Model for the Dielectric Function of Amorphous Material

D. K. Lynch (The Aerospace Corp.)

Though lacking in long range order, amorphous materials possess significant short range order that is geometrically very similar to their crystalline counterparts. As a result, it is possible to estimate the dielectric function of amorphous materials from the materials' crystalline optical constants using a simple transform. The technique assumes that there is a continuous distribution of oscillators (CDO), each with its own resonant frequency. The distribution in frequencies is a result of a parallel distribution in ionic spacing. By convoluting the crystalline permittivity with a suitable function representing the distribution of resonant frequencies, we demonstrate that the dielectric functions for amorphous quartz and olivine can be computed with reasonable accuracy. The technique provides a simple means of computing the gross influence of atomic disorder on spectral characteristics of cosmic dust.

Program listing for Thursday