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Optoelectronic pressure dependent study of MgZrO₃ oxide and ground state thermoelectric response using Ab-initio calculations

Noor Naveed Ahmed, Rashid Muhammad Abdul Rehman, Mahmood Qasim, Ul-Haq Bakhtiar, Naeem M. A., Laref Amel

Opto-Electronics Review

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2019

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Vol. 27, No. 2

194--201

EN

The electronic, optical and thermoelectric properties of zirconia-based MgZrO₃ oxide have been studied theoretically at a variant pressure up to 25 GPa. Calculations for the formation energy and tolerance factor reveal the thermodynamic and structural stability of MgZrO₃. To tune the indirect band gap from to a direct band gap, the optimized structure of MgZrO₃ has been subjected to external pressure up to 25 GPa. The optical properties have been discussed in the form of dielectric constant and refraction that brief us about the dispersion, polarization, absorption, and transparency of the MgZrO₃. In the end, the thermoelectric parameters have been analyzed at variant pressure against the chemical potential and temperature. The narrow band gap and high absorption in the ultraviolet region increase the demand of the studied oxide for energy harvesting device applications.

2

A density functional theory study of Raman modes of cadmium hexathiohypodiphosphate (CdPS3)

Shakoor A., Hussain F., Hassan N ., Majid A., Bhatti M. T., Siddique H.

Materials Science Poland

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2015

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Vol. 33, No. 2

286--291

EN

Raman scattering investigations based on density functional theory (DFT) calculations were performed to explore the vibrational modes of a cadmium hexathiohypodiphosphate CdPS3 single crystal. The calculations were performed to obtain the Raman spectra for the cadmium hexathiohypodiphosphate atoms to study the size dependence. Several vibrational modes indicating stretching and bending features related to Cd, S and P atoms were observed. Modifications of the frequency and intensity of different Raman modes with an increase in the number of atoms in CdPS3 were discussed in detail. Hydrogen atoms were added in order to make the closed shell configuration and saturate the CdPS3 as per the requisite for calculating the Raman spectra. This produced some additional modes of vibration related to hydrogen atoms. Band gap and formation energy were also calculated. The results generated are found to be in close agreement with the experimental values.

3

Bonding xenon on the surface of uranium dioxide single crystal

Dąbrowski L., Szuta M.

Nukleonika

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2013

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Vol. 58, No. 4

453--458

EN

We present density functional theory (DFT) calculation results of xenon atom interaction with the surface of uranium dioxide single crystal. A pseudo-potential approach in the generalized gradient approximation (GGA) was applied using the ABINIT program package. It has been revealed that close to the surface a potential well is formed for xenon atom due to its interaction with the atoms of oxygen and uranium. Depth and shape of the well is the subject of “ab initio” calculations. The calculations were performed both for the case of oxygenic and metallic surfaces. It has been shown, that the potential well for the oxygenic surface is deeper than for the metallic surface.

4

EPR study on sugar radicals utilized for detection of radiation treatment of food

Guzik G. P., Stachowicz W., Michalik J.

Nukleonika

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2012

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Vol. 57, No. 4

545-549

EN

Radicals produced by ionizing radiation in sugars, the components of dried and raw fruits give rise to stable multicomponent electron paramagnetic resonance (EPR) signals unidentified so far. The subject of the present EPR study is to identify the radicals stabilized in gamma-irradiated crystalline sugars, D(+)mannose and L(-)sorbose extracted from cranberries (Vaccininum oxycoccos) and rowan berries (Sorbus aucuparia), respectively. EPR measurements and density functional theory (DFT) simulations were employed for that purpose.