Vacuum Ultraviolet Absorption Bands of Ag-Doped Alkali Halides

Layer-by-layer films of poly (allylamine hydrochloride) (PAH) and graphene oxide (GO) were characterized, looking at growth with the number of bilayers, morphology, and electrical properties. The PAH/GO films revealed a linear increase in absorbance with the increase in the number of deposited bilayers, allowing the determination that 10.7 ± 0.1 mg m−2 of GO is adsorbed per unit of area of each bilayer. GO absorption bands at 146, 210, 247 and 299 nm, assigned to π-π* and n-π* transitions in the aromatic ring (phenol) and of the carboxylic group, respectively, were characterized by vacuum ultraviolet spectroscopy. The morphological characterization of these films demonstrated that they are not completely uniform, with a bilayer thickness of 10.5 ± 0.7 nm. This study also revealed that the films are composed of GO and/or PAH/GO fibers and that GO is completely adsorbed on top of PAH. The electrical properties of the films reveal that PAH/GO films present a semiconductor behavior. In addition, a slight decrease in conduction was observed when films were prepared in the presence of visible light, likely due to the presence of oxygen and moisture that contributes to the damage of GO molecules.

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Vacuum ultraviolet absorption spectra of solid N2O and CO2 at 53 K

The Journal of Chemical Physics ◽

10.1063/1.431496 ◽

1975 ◽

Vol 63 (4) ◽

pp. 1676-1681 ◽

Cited By ~ 18

Author(s):

Kevin M. Monahan ◽

William C. Walker

Keyword(s):

Absorption Spectra ◽

Vacuum Ultraviolet ◽

Ultraviolet Absorption

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Vacuum ultraviolet absorption spectra of some chloroalkanes

Journal of the American Chemical Society ◽

10.1021/ja00813a011 ◽

1974 ◽

Vol 96 (6) ◽

pp. 1708-1712 ◽

Cited By ~ 22

Author(s):

J. W. Raymonda ◽

L. O. Edwards ◽

B. R. Russell

Keyword(s):

Absorption Spectra ◽

Vacuum Ultraviolet ◽

Ultraviolet Absorption

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Magneto-optical properties of defect centres in alkali halide crystals

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1967.0158 ◽

1967 ◽

Vol 300 (1460) ◽

pp. 78-93 ◽

Cited By ~ 32

Keyword(s):

Optical Absorption ◽

Silver Atom ◽

Alkali Halides ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Coupling Constant ◽

Absorption Bands ◽

Optical Effects ◽

Alkali Halide Crystals ◽

Defect Centres

Zeeman spectroscopy is not practicable for the investigation of the structure of electronic conventional states which give rise to broad optical absorption bands in solids. We have investigated the application of Faraday rotation and circular dichroism techniques to absorption bands of neutral silver atoms and F centres in alkali halides. These centres give rise to optical absorption bands due to transitions of the type 2 S → 2 P which are 2000 to 6000 cm -1 in width because, in part, of strong coupling to lattice phonons. A discussion is given of information which may be obtained concerning the electonic states involved in the 2 S → 2 P transition by analysis of the magneto-optical effects by the method of moments. It is shown, for example, that the spin-orbit coupling constant of the 2 P state of the silver atom is reduced from 613 cm -1 in the free state to 365 cm -1 in KCl, to 102 cm -1 in KBr and to an unmeasurably small value in KI. This cancellation of spin-orbit interaction of the silver atom is assigned to symmetry allowed admixtures of lattice ion wavefunctions into the 2 P state.

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