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Browsing Research Articles (Physics) by Type "Postprint Article"
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Mapasha, Refilwe Edwin; Ukpong, Aniekan M.; Chetty, Nithaya
(American Physical Society, 2012-05)
We present a comparative density functional study of the adsorption of hydrogen on bilayer graphene. Six different exchange-correlation functionals are employed to explore the possible configurations of hydrogen ad- sorption ...
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Mapasha, Refilwe Edwin; Molepo, Mahlanga P.; Chetty, Nithaya
(Elsevier, 2016-05)
We present a density functional study of various hydrogen vacancies located on a single hexagonal ring of graphane (fully hydrogenated graphene) considering the e ects of charge states and the position of the Fermi level. ...
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Mapasha, Refilwe Edwin; Chetty, Nithaya
(Elsevier, 2010-06)
We study Li on graphene using the Vienna ab initio Simulation Package employing the projector-augmented wave method within the generalized gradient approximation for the exchange-correlation potential. We give detailed ...
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Igumbor, Emmanuel; Mapasha, Refilwe Edwin; Meyer, Walter Ernst
(Springer, 2017-07)
The results of an ab initio modelling of aluminium substitutional impurity
(AlGe), aluminium interstitial in Ge [IAl for the tetrahedral (T) and hexagonal
(H) configurations] and aluminium interstitial-substitutional ...
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Ouma, C.N.M.; Meyer, Walter Ernst
(Elsevier, 2014-04)
Density functional theory (DFT) within the generalized gradient approximation (GGA) has been used to study the structural and electronic properties of
Eu3þ defect complexes in GaN under Ga-rich conditions. Two distinct ...
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Igumbor, Emmanuel; Omotoso, Ezekiel; Meyer, Walter Ernst
(Trans Tech Publications, 2017-06)
We present results of defect formation energies and charge state thermodynamic transition levels of Mg and Te interstitials in MgTe wurzite structure. We use the generalized gradient approximation and local density ...
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Igumbor, Emmanuel; Ouma, C.N.M.; Webb, Geoffrey; Meyer, Walter Ernst
(Elsevier, 2016-01)
In this work, we present ab-initio calculation results of Ge di-interstitials (I2(Ge)) in the framework of the density functional theory (DFT) using the Heyd, Scuseria, and Ernzerhof (HSE) hybrid functional. The formation ...
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Igumbor, Emmanuel; Obodo, Kingsley Onyebuchi; Meyer, Walter Ernst
(Trans Tech Publications, 2016)
We present detailed calculations of formation and thermodynamics transition state
energies of Mgi and Sei interstitial defects in MgSe using generalized gradient approximation
(GGA) and local density approximation (LDA) ...
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Fru, Juvet Nche; Diale, M. (Mmantsae Moche)
(Elsevier, 2024-03)
Please read abstract in the article.
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Nothling, Johan Oliviette; Mancal, T.; Kruger, T.P.J. (Tjaart)
(American Institute of Physics, 2025-01)
Much can be learned about molecular aggregates by modeling their fluorescence-type spectra. In this study, we systematically describe the accuracy of various methods for simulating fluorescence-type linear spectra in a ...
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Momodu, Damilola Y.; Madito, M.J. (Moshawe); Barzegar, Farshad; Bello, Abdulhakeem; Khaleed, Abubakar A.; Olaniyan, Okikiola; Dangbegnon, Julien K.; Manyala, Ncholu I.
(Springer, 2017-03)
Activated carbon from tree bark (ACB) has been
synthesized by a facile and environmentally friendly activation
and carbonization process at different temperatures (600,
700 and 800 °C) using potassium hydroxide (KOH) ...
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Adeola, Adedapo Oluwasanu; Iwuozor, Kingsley O.; Akpomie, Kovo G.; Adegoke, Kayode Adesina; Oyedotun, Kabir Oyeniran; Ighalo, Joshua O.; Amaku, James F.; Olisah, Chijioke; Conradie, Jeanet
(Springer, 2023-06)
Please read abstract in the article.
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Akande, Amos A.; Mosuang, Thuto; Ouma, Cecil N.M.; Benecha, Evans M.; Tesfamicheal, Tuquabo; Roro, Kittessa T.; Machatine, Augusto Gonçalo Jose; Mwakikunga, Bonex Wakufwa
(Elsevier, 2020-04)
Please read abstract in the article.
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Mtangi, Wilbert; Janse van Rensburg, Pieter Johan; Diale, M. (Mmantsae Moche); Auret, Francois Danie; Nyamhere, Cloud; Nel, Jacqueline Margot; Chawanda, Albert
(Elsevier, 2010-07)
Current-voltage characteristics of Au/Ni/n-GaN Schottky contacts have been measured in the
60-320 K temperature range. The zero bias barrier height, bo and ideality factor, n have been
studied as a function of temperature. ...
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Mayimele, Meeheketo Advice; Auret, Francois Danie; Janse van Rensburg, J.P.; Diale, M. (Mmantsae Moche)
(Elsevier, 2016-01)
We report on the analysis of current voltage (I-V) measurements performed on Pd/ZnO
Schottky barrier diodes (SBDs) in the 80-320 K temperature range. Assuming thermionic
emission (TE) theory, the forward bias I-V ...
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Rakityansky, Sergei Anatoljevich; Elander, N.
(Institute of Physics, 2012-03)
For a two-dimensional quantum-mechanical problem, we obtain a generalized
power series expansion of the S-matrix that can be done near an arbitrary point
on the Riemann surface of the energy, similar to the standard ...
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Duvenhage, Rocco de Villiers; Van Staden, Wernd; Wuzyk, Jan
(Elsevier, 2018-02)
We study a first variation formula for the eigenvalues of the Laplacian evolving under the Ricci flow in a simple example of a noncommutative matrix geometry, namely a finite dimensional representation of a noncommutative ...
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Mtangi, Wilbert; Nel, Jacqueline Margot; Auret, Francois Danie; Chawanda, Albert; Nyamhere, Cloud; Diale, M. (Mmantsae Moche)
(Elsevier, 2012-10)
We report on the studies carried out on hydrogen peroxide treated melt grown, bulk single
crystal ZnO samples. Results show the existence of two shallow donors in the as-received
ZnO samples with energy levels (37.8 ± ...
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Hlatshwayo, Thulani Thokozani; Sebitla, L.D.; Njoroge, Eric Gitau; Mlambo, Mbuso; Malherbe, Johan B.
(Elsevier, 2017-03)
The migration behaviour of cadmium (Cd) implanted into glassy carbon and the effects of annealing on radiation damage introduced by ion implantation were investigated. The glassy carbon substrates were implanted with Cd ...
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Ilioaia, Cristian; Kruger, T.P.J. (Tjaart); Ilioaia, Oana; Robert, Bruno; Van Grondelle, Rienk; Gall, Andrew
(Elsevier, 2018-02)
It has already been established that the quaternary structure of the main light-harvesting complex (LH2) from the photosynthetic bacterium Rhodopseudomonas palustris is a nonameric ‘ring’ of PucAB heterodimers and under ...