Densification of Sio Gel Films by Synchrotron Radiation and its Dependence on Photon Energy

1994 ◽  
Vol 375 ◽  
Author(s):  
Hiroaki Imai ◽  
Koichi Awazu ◽  
Masaru Yasumori ◽  
Hiroshi Hirashima ◽  
Hideo Onuki

AbstractThe interaction of synchrotron radiation (SR) emitted from a polarizing undulator with SiO2 gel films was investigated by ellipsometry and infrared spectroscopy. The photon energy in SR was varied in the range of 6.4−17.8 eV using an Onuki-type undulator in order to study the energy dependence of the interaction. We found that an increase of refractive index, a decrease of thickness of the films and a loss of OH groups were induced by photons with energies above ˜9 eV although any changes were not observed with photons below ˜7 eV. These results suggest that SiO2 gel films are densified through electronic processes stimulated by the energetic photons.

1982 ◽  
Vol 47 (4) ◽  
pp. 1060-1068 ◽  
Author(s):  
Vojtěch Bekárek ◽  
Jan Juřina

Dependence of ET(30) of solvent parameters on relative permittivity (ε) and refractive index (n) of solvent has been found for forty solvents in the form ET(30)=29.87 + 72.03 (ε - 1/(2ε + 1)-29.16(ε - 1) (n 2 - 1)/(2ε + 1) (2n2 + 1), the correlation coefficient being 0.958. Relation has been discussed between ET(30) and π solvent parameters and significance of the term (ε - 1). (n2 - 1)/(2ε + 1) (2n2 + 1) has been tested for evaluation of solvent effects in electronic spectra.>


2010 ◽  
Vol 181 (2-3) ◽  
pp. 193-196 ◽  
Author(s):  
Masaru Takizawa ◽  
Hidetoshi Namba ◽  
Fumihiko Matsui ◽  
Hiroshi Daimon

2020 ◽  
Vol 27 (1) ◽  
pp. 75-82
Author(s):  
Mikhail Svechnikov ◽  
Nikolay Chkhalo ◽  
Alexey Lopatin ◽  
Roman Pleshkov ◽  
Vladimir Polkovnikov ◽  
...  

In this work, the refractive index of beryllium in the photon energy range 20.4–250 eV was experimentally determined. The initial data include measurements of the transmittance of two free-standing Be films with thicknesses of 70 nm and 152 nm, as well as reflectometric measurements of similar films on a substrate. Measurements were carried out at the optics beamline of the BESSY II synchrotron radiation source. The absorption coefficient β was found directly from the transmission coefficient of the films, and the real part of the polarizability δ was calculated from the Kramers–Kronig relations. A comparison is carried out with results obtained 20 years ago at the ALS synchrotron using a similar methodology.


Sign in / Sign up

Export Citation Format

Share Document