Tl. Roush, OPTICAL-CONSTANTS OF AMORPHOUS-CARBON IN THE MID-IR (2.5-25 MU-M, 4000-400 CM(-1)), Planetary and space science, 43(10-11), 1995, pp. 1297-1301
Laboratory measurement of the Fresnel reflectance are used to derive t
he real and imaginary indices of refraction of amorphous carbon in the
2.5-25 mu m region. Comparison to previously reported optical constan
ts, derived from extinction measurements at these wavelengths, show bo
th similarities and differences. The differences are likely due to the
different samples studied. wavelength-dependent calculated extinction
coefficients (Q(ext)/a) from these values derived here are intermedia
te in value to previously reported Q(ext)/a other amorphous carbon sam
ples. The overall spectral shape exhibits a lambda(-a) behavior with a
lpha = 1.05 +/- 0.05. However, more spectral structure is seem in the
18-25 mu m region than has been reported previously.