The coupling between the Monte Carlo （MC） method and geometrical optics to improve accuracy is investigated. The results obtained show improved agreement with previous experimental data, demonstrating that the MC me...The coupling between the Monte Carlo （MC） method and geometrical optics to improve accuracy is investigated. The results obtained show improved agreement with previous experimental data, demonstrating that the MC method, when coupled with simple geometrical optics, can simulate multiple scattering with enhanced fidelity.展开更多
The Si L2,3 X-ray absorption near-edge structure (XANES) can be used to probe thelocal structure around Si and derive electronic information of the unoccupied s- andd-like partial density of states in nano-size SiO2. ...The Si L2,3 X-ray absorption near-edge structure (XANES) can be used to probe thelocal structure around Si and derive electronic information of the unoccupied s- andd-like partial density of states in nano-size SiO2. We present Si L2,3-edge for threedifferent size silicates acquired by total electron yield (TEY) at the photoemission sta-tion of Beijing Synchrotron Radiation Facility (BSRF). The Si L2,3-edge spectra areinterpreted based on ab initio full multiple-scattering (MS) calculation. The Si L2.3-edge of nano-size materials has XANES similar to that of a-quartz. The similaritiesbetween the Si L2.3-edge shapes attest to a common molecular-orbital picture of theirSi-O bonding and the same coordination state. However, a considerable broadeningof Si L2,3-edge XANES spectra as decrease of particle size is also an indicative ofpolyhedral distortions.展开更多
文摘The coupling between the Monte Carlo （MC） method and geometrical optics to improve accuracy is investigated. The results obtained show improved agreement with previous experimental data, demonstrating that the MC method, when coupled with simple geometrical optics, can simulate multiple scattering with enhanced fidelity.
基金supported by 100-Tatlent Research Program of The Chinese Academy of Sciencesthe Natinal Natural Science Foundation of China(NSFC)for financial support(Grant No.10074063)The Chinese Academy of Sciences(No.KJ952-S1-418)
文摘The Si L2,3 X-ray absorption near-edge structure (XANES) can be used to probe thelocal structure around Si and derive electronic information of the unoccupied s- andd-like partial density of states in nano-size SiO2. We present Si L2,3-edge for threedifferent size silicates acquired by total electron yield (TEY) at the photoemission sta-tion of Beijing Synchrotron Radiation Facility (BSRF). The Si L2,3-edge spectra areinterpreted based on ab initio full multiple-scattering (MS) calculation. The Si L2.3-edge of nano-size materials has XANES similar to that of a-quartz. The similaritiesbetween the Si L2.3-edge shapes attest to a common molecular-orbital picture of theirSi-O bonding and the same coordination state. However, a considerable broadeningof Si L2,3-edge XANES spectra as decrease of particle size is also an indicative ofpolyhedral distortions.
