Electronic and Optical Properties of Magnesium Phthalocyanine (MgPc) Solid Films Studied by Soft X-Ray Excited Optical Luminescence and X-Ray Absorption Spectroscopies

2008 ◽  
Vol 130 (39) ◽  
pp. 13008-13012 ◽  
Author(s):  
N. Peltekis ◽  
B. N. Holland ◽  
S. Krishnamurthy ◽  
I. T. McGovern ◽  
N. R. J. Poolton ◽  
...  
Keyword(s):  
Optical Properties ◽  
X Ray ◽  
Electronic And Optical Properties ◽  
Solid Films ◽  
Optical Luminescence ◽  
X Ray Absorption

Origin of luminescence from ZnO/CdS core/shell nanowire arrays

Nanoscale ◽  
2014 ◽  
Vol 6 (16) ◽  
pp. 9783-9790 ◽  
Author(s):  
Zhiqiang Wang ◽  
Jian Wang ◽  
Tsun-Kong Sham ◽  
Shaoguang Yang
Keyword(s):  
Optical Properties ◽  
Chemical Imaging ◽  
Nanowire Arrays ◽  
Nano Composites ◽  
Core Shell ◽  
Edge Structure ◽  
X Ray ◽  
Optical Luminescence ◽  
Scanning Transmission ◽  
X Ray Absorption

Chemical imaging, electronic structure and optical properties of ZnO/CdS nano-composites have been investigated using scanning transmission X-ray microscopy (STXM), X-ray absorption near-edge structure (XANES) and X-ray excited optical luminescence (XEOL) spectroscopy.

X-ray absorption spectroscopy and density functional analysis of the Fe3+ distribution profile on Al sites in a chrysoberyl crystal, BeAl2O4:Fe3+

2016 ◽  
Vol 49 (2) ◽  
pp. 385-388 ◽  
Author(s):  
Kanokwan Kanchiang ◽  
Atipong Bootchanont ◽  
Janyaporn Witthayarat ◽  
Sittichain Pramchu ◽  
Panjawan Thanasuthipitak ◽  
...  
Keyword(s):  
Optical Properties ◽  
Absorption Spectroscopy ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Distribution Profile ◽  
Laser Applications ◽  
Edge Structure ◽  
X Ray ◽  
Site Distribution ◽  
X Ray Absorption

Chrysoberyl is one of the most interesting minerals for laser applications, widely used for medical purposes, as it exhibits higher laser performance than other materials. Although its utilization has been vastly expanded, the location of transition metal impurities, especially the iron that is responsible for chrysoberyl's special optical properties, is not completely understood. The full understanding and control of these optical properties necessitates knowledge of the precise location of the transition metals inside the structure. Therefore, synchrotron X-ray absorption spectroscopy (XAS), a local structural probe sensitive to the different local geometries, was employed in this work to determine the site occupation of the Fe3+ cation in the chrysoberyl structure. An Fe K-edge X-ray absorption near-edge structure (XANES) simulation was performed in combination with density functional theory calculations of Fe3+ cations located at different locations in the chrysoberyl structure. The simulated spectra were then qualitatively compared with the measured XANES features. The comparison indicates that Fe3+ is substituted on the two different Al2+ octahedral sites with the proportion 60% on the inversion site and 40% on the reflection site. The accurate site distribution of Fe3+ obtained from this work provides useful information on the doping process for improving the efficiency of chrysoberyl as a solid-state laser material.

The structure and bonding properties of tiopronin-protected silver nanoparticles as studied by X-ray absorption spectroscopy

2018 ◽  
Vol 96 (7) ◽  
pp. 749-754 ◽  
Author(s):  
J. Daniel Padmos ◽  
David J. Morris ◽  
Peng Zhang
Keyword(s):  
Optical Properties ◽  
Absorption Spectroscopy ◽  
Structural Changes ◽  
Chemical Properties ◽  
Structure Property ◽  
Ag Nps ◽  
X Ray ◽  
Ligand Shell ◽  
Bonding Properties ◽  
X Ray Absorption

Thiolate-protected Ag nanoparticles (NPs) exhibit interesting physical and chemical properties which may lead to various sensing, diagnostic, and therapeutic applications. Further, understanding structure–property relationships of Ag NPs is of great interest to optimize their application. Herein, we used TEM, UV–vis, and a series of synchrotron X-ray spectroscopy techniques to probe the local structure and chemical bonding properties of thiolate-stabilized Ag NPs. Compared with other Ag nanostructures prepared under slightly modified conditions, the Ag NPs were found to have pronounced structural changes, which led to immensely different optical properties. Notably, the NPs were also found to have similar surface structure to recently elucidated Ag nanoclusters prepared with different thiolates. These findings suggest that the NP structure and optical properties can be sensitively tailored by controlling the synthetic conditions. The multi-element, multi-core excitation approach (i.e., Ag K-, Ag L3-, and S K-edges) employed in the X-ray absorption spectroscopy measurements was also demonstrated as an effective tool to uncover the NP structure from both the metal core and the ligand shell perspectives.

scholarly journals Impact of Lithium Composition on Structural, Electronic and Optical Properties of Lithium Cobaltite Prepared by Solid-state Reaction

2014 ◽  
Vol 6 (2) ◽  
pp. 217-231 ◽  
Author(s):  
F. Khatun ◽  
M. A. Gafur ◽  
M. S. Ali ◽  
M. S. Islam ◽  
M. A. R. Sarker
Keyword(s):  
Optical Properties ◽  
Solid State ◽  
Ionic Conductivity ◽  
Cathode Material ◽  
Solid State Reaction ◽  
Layered Crystal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electronic And Optical Properties ◽  
Lithium Cobaltite

The lithium-cobalt oxide LixCoO2 is a promising candidate as highly active cathode material of lithium ion rechargeable batteries. The crystalline-layered lithium cobaltite has attracted increased attention due to recent discoveries of some extraordinary properties such as unconventional transport and magnetic properties. Due to layered crystal structure, Li contents (x) in LixCoO2 might play an important role on its interesting properties. LiCoO2 crystalline cathode material was prepared by using solid-state reaction synthesis, and then LixCoO2 (x<1) has been synthesized by deintercalation of produced single-phase powders. Structure and morphology of the synthesized powders were investigated by X-ray diffraction (XRD), Infrared spectroscopy, Impedance analyzer etc. The influence of lithium composition (x) on structural, electronic and optical properties of lithium cobaltite was studied. Temperature dependent electrical resistivity was measured using four-probe technique. While LixCoO2 with x = 0.9 is a semiconductor, the highly Li-deficient phase (0.75 ? x ? 0.5) exhibits metallic conductivity. The ionic conductivity of LixCoO2 (x = 0.5 – 1.15) was measured using impedance spectroscopy and maximum conductivity of Li0.5CoO2 was found to be 6.5×10-6 S/cm at 273 K. The properties that are important for applications, such as ionic conductivity, charge capacity, and optical absorption are observed to increase with Li deficiency. Keywords: Calcination; Characterization; Inorganic compounds; Solid-State reaction; X-ray diffraction. © 2014 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v6i2.17900 J. Sci. Res. 6 (2), 217-231 (2014)  

VUV- and Soft X-Ray-Induced Optical Luminescence and X-Ray Absorption Fine Structures of Porous Silicon

1992 ◽  
Vol 281 ◽  
Author(s):  
T. K. Sham ◽  
D. T. Jiang ◽  
I. Coulthard ◽  
J. W. Lorimer ◽  
X. H. Feng ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Total Electron Yield ◽  
Total Electron ◽  
X Ray ◽  
Absorption Fine ◽  
Electron Yield ◽  
Optical Luminescence ◽  
Fine Structures ◽  
X Ray Absorption ◽  
Uv Excitation

ABSTRACTOptical luminescence in porous silicon induced by soft X-ray and vacuum UV excitation with energies in the vicinity of the Si K-edge (1838 eV) and the Si L-edge (99 eV) has been observed. The luminescence has been used, together with total electron yield, to record X-ray absorption fine structure (XAFS) in the near-edge region of both Si edges. The near- edge spectra recorded simultaneously with either luminescence or total electron yield were compared, and the implications of these measurements for the structure of porous silicon are discussed.

Sign in / Sign up

Export Citation Format

Share Document