scholarly journals Fast optical absorption spectra calculations for periodic solid state systems

Author(s):  
Felix Henneke ◽  
Lin Lin ◽  
Christian Vorwerk ◽  
Claudia Draxl ◽  
Rupert Klein ◽  
...  
2009 ◽  
Vol 2009 (7) ◽  
pp. 430-432 ◽  
Author(s):  
Hua-Long Chen ◽  
Han-Mao Kuang ◽  
Wen-Tong Chen ◽  
Shao-Ming Ying ◽  
Jiu-Hui Liu

The compound [Hg3S2CI2] has been obtained by solid-state reactions. It crystallises in the acentric space group R3 of the rhombohedral system with six formula units in a cell [ a = b = 12.654(3), c = 7.753(4) Å, V = 1075.1(6) Å3, CI2Hg3S2, M r = 736.79, D c = 6.828 g cm−3, S = 0.987, μ(Mo Kα) = 65.308 mm−1, F(000) = 1836, R = 0.0631 and wR = 0.1443] and is characterised by a 3-D framework structure, which is composed of interconnected right-handed helices formed by tetrahedral Hg atoms. Optical absorption spectra reveal the presence of an optical bandgap of 2.51 eV and the composition Hg3S2CI2 is confirmed by semiquantitative microscope analysis.


1989 ◽  
Vol 164 ◽  
Author(s):  
K. L. Moran ◽  
W. T. A. Harrison ◽  
T. E. Gier ◽  
J. E. Mac Dougall ◽  
G. D. Stucky

AbstractSolid-state chemistry has been used to control both the size and the interconnection distance of small II-VI semiconductor moeities incorporated in zeolitic hosts with the sodalite-type structure. Structural characterization was carried out using X-ray Rietveld powder methods, and optical properties of these materials were also measured. These novel materials show quantum superlattice effects as evidenced by blue shifts in their optical absorption spectra.


2014 ◽  
Vol 548-549 ◽  
pp. 124-128 ◽  
Author(s):  
S. Insiripong ◽  
S. Kaewjeang ◽  
U. Maghanemi ◽  
H.J. Kim ◽  
N. Chanthima ◽  
...  

In this work, properties of Nd3+ in Gd2O3-CaO-SiO2-B2O3 glass systems with composition 25Gd2O3-10CaO-10SiO2-(55-x)B2O3-xNd2O3 where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol% were investigated. The optical absorption spectra show peaks at 4F3/2 (877 nm) , 4F5/2+2H9/2 (802 nm), 4F7/2+4S3/2 (743 nm), 4F9/2 (682 nm), 2H11/2 (627 nm), 2G7/2 +4G5/2 (582 nm), 4G7/2 +2K13/2 (527 nm), 4G11/2 (481 nm), 2P1/2 (427 nm) and 2L15/2 + 4D1/2 + 1I11/2+ 4D5/2+ 4D3/2 (355 nm) reflecting the Nd3+ ions in glass matrices. The densities were increased with increasing of Nd2O3 concentration. This indicates the increase of the molecular weight by the replacement of B2O3 with a heavier Nd2O3 oxide in the glass. The upconversion luminescence spectra show bands at 393 nm for all Nd2O3 concentration and the strongest intensity from 2.5 % mol of Nd2O3 was obtained. For NIR luminescence, the intensity of Nd3+ emission spectra increases with increasing concentrations of Nd3+ up to 1.5 mol% and beyond 1.5 mol% the concentration quenching is observed.


1962 ◽  
Vol 40 (10) ◽  
pp. 1480-1489 ◽  
Author(s):  
J. W. Bichard ◽  
J. C. Giles

The optical absorption spectra of arsenic and phosphorus donor impurities in silicon have been studied under conditions of improved resolution. Absorption lines due to transitions from the impurity ground state to the excited states 2p0, 2p±, 3p0, 3p±, 4p0, 4 p±, and 5p0, and 5p± have been observed at 4.2° K. The relative intensities of some of these absorption lines are compared with existing experimental and theoretical estimates. The contribution of instrumental broadening to the observed line widths is assessed and natural line widths are estimated. The estimates indicate values for the natural line widths which are much less than those previously reported. For phosphorus impurity, the natural line widths are estimated to be less than 0.08 × 10−3 electron volts full width at half-maximum. The possibility of concentration broadening is discussed in connection with the arsenic data.


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