Optical constants of amorphous for photons in the range of 60-3000 eV

Abstract

Optical constants of amorphous have been calculated by the Kramers-Kronig analysis in the continuous spectral region including , O K and Si K absorption edges from the reflection spectra measured using synchrotron radiation. It is the first experiment carried out in such a wide energy region with the same sample. It has been found that for extrapolation of the experimental curve in the high energy region, where the photon energy exceeds the ionization potential of the Si K edge, the relation can be used for energies such that at small grazing angles.

Elastic light scattering from free sub-micron particles in the soft X-ray regime

“…The fine structure in the 100-125 eV regime, corresponding to the highly dispersive part of the complex refraction index, taken from ref. [24], is well reproduced by the present model results on variable-size nanoparticles. However, the results shown in Fig.…”

“…There are, however, characteristic changes in amplitudes of the spectral features, as is evident from a comparison between a 4% and an 8% distribution, indicating that an 8% size distribution is too wide. A comparison with previous work on amorphous SiO2 [24] indicates that the clearly split feature near 105 eV, as shown in Fig. 6, also occurs.…”

“…Therefore, we discount this assignment. Further, additional fits to the experimental results using pure Mie theory by varying the index of refraction of the spheres, which are different from published values, [24] also failed. They give similarly large values of n 1, which is unlike the published values ranging between 0.97 and 0.99 in the energy regime under investigation.…”

“…6, which are in agreement with earlier results. [20,23,24] Details on the spectral assignments of the near-edge features can be found in these previous works. Additional experiments indicate that the near-edge spectra of differently-sized silica particles do not show any particle size dependence.…”

“…The dashed curves correspond to the modelled spectra using a pure Mie model including the size distributions compiled in Table 1 along with the optical constants taken from ref. [24]. The near-edge spectrum (NEXAFS) at the top of the Figure is obtained from total electron yield measurements of 150 nm silica particles.…”