Infrared reflection spectra of forsterite crystal
H. Sogawa, C. Koike, H. Chihara, H. Suto, S. Tachibana, A. Tsuchiyama, and T. Kozasa
Astronomy and Astrophysics, 451, 357-361, 2006

In the infrared wavelength region, we assumed that the dielectric funtion of crystal is represented by the dispersion relation with the multiple oscillator model, which is given as

$\displaystyle \epsilon$($\displaystyle \omega$) = $\displaystyle \epsilon_{0}^{}$ + $\displaystyle \sum_{i}^{}$$\displaystyle {\frac{{\omega_{pi}^2}}{{\omega_i^2 - \omega^2 - i\gamma_i\omega}}}$, (1)

where $ \epsilon$($ \omega$) is a complex dielectric function for the frequency $ \omega$, $ \epsilon_{0}^{}$ is the dielectric constant at the high-frequency limit, and $ \omega_{i}^{}$, $ \omega_{{pi}}^{2}$, and $ \gamma_{i}^{}$ respectively represent the resonance frequency, the oscillator strength, and the damping constant of the i-th oscillator.

Table 1: Oscillator Parameters for IR bands of forsterite crystal
B1u $ \epsilon_{0}^{}$=2.71
$ \omega_{j}^{}$(cm-1) $ \omega_{{pj}}^{2}$/$ \omega_{j}^{2}$ $ \gamma_{j}^{}$/$ \omega_{j}^{}$
873.8 0.62 0.0058
502.2 0.45 0.021
476.3 0.16 0.017
415.1 1.02 0.015
408.4 0.42 0.013
304.5 0.026 0.014
291.2 1.26 0.011
276.1 0.074 0.0093
B2u $ \epsilon_{0}^{}$=2.66
$ \omega_{j}^{}$(cm-1) $ \omega_{{pj}}^{2}$/$ \omega_{j}^{2}$ $ \gamma_{j}^{}$/$ \omega_{j}^{}$
984.2 0.0071 0.0053
872.5 0.40 0.0055
838.8 0.11 0.0096
526.5 0.18 0.025
505.9 0.042 0.012
455.8 0.19 0.020
416.4 0.28 0.015
395.0 0.47 0.014
348.2 1.21 0.017
288.6 1.65 0.016
276.5 0.11 0.012
143.4 0.075 0.014
B3u $ \epsilon_{0}^{}$=2.77
$ \omega_{j}^{}$(cm-1) $ \omega_{{pj}}^{2}$/$ \omega_{j}^{2}$ $ \gamma_{j}^{}$/$ \omega_{j}^{}$
976.4 0.33 0.0064
957.9 0.17 0.0040
841.0 0.0029 0.0085
603.8 0.23 0.021
501.5 0.35 0.025
402.6 1.56 0.015
379.1 0.95 0.015
319.5 0.079 0.0084
294.0 0.32 0.012
274.6 0.054 0.011
200.8 0.027 0.014

Text data of table 1.