Accurate formation energies of charged defects in solids: A systematic approach

Download
2017-06-30
Vinichenko, Dmitry
Sensoy, Mehmet Gokhan
Friend, Cynthia M.
Kaxiras, Efthimios
Defects on surfaces of semiconductors have a strong effect on their reactivity and catalytic properties. The concentration of different charge states of defects is determined by their formation energies. First-principles calculations are an important tool for computing defect formation energies and for studying the microscopic environment of the defect. The main problem associated with the widely used supercell method in these calculations is the error in the electrostatic energy, which is especially pronounced in calculations that involve surface slabs and two-dimensional materials. We present an internally consistent approach for calculating defect formation energies in inhomogeneous and anisotropic dielectric environments and demonstrate its applicability to the cases of the positively charged Cl vacancy on the NaCl (100) surface and the negatively charged S vacancy in monolayer MoS2.
PHYSICAL REVIEW B

Suggestions

Electrical transport, optical and thermal properties of polyaniline-pumice composites
YILMAZ, KORAY; Akgoz, A.; Cabuk, M.; Karaagac, H.; KARABULUT, ORHAN; YAVUZ, Mustafa (2011-11-01)
In this study, electrical conductivity, photoconductivity, absorbance and thermal properties of polyaniline (PANI) and polyaniline-pumice composites were investigated. Temperature dependent conductivity and photoconductivity measurements were carried out in the temperature range of 80-400K. The measurements revealed that the dominant conduction mechanisms in polyaniline and 15% pumice doped composite were hopping conduction. The low activation energies calculated for 36% pumice doped composite indicated tha...
Optical characterization of silicon based hydrogenated amorphous thin films by un-visible and infrared measurements
Kılıç, İlker; Katırcıoğlu, Bayram; Department of Physics (2006)
Various carbon content hydrogenated amorphous silicon carbide (a-Si1ŁxCx:H) and hydrogenated amorphous silicon (a-Si:H) thin films have been deposited on various substrates by using plasma enhanced chemical vapour deposition (PECVD) technique. Transmission spectra of these films have been determined within UV-Visible region and the obtained data were analysed to find related physical constants such as; refractive indices, thicknesses, etc. Fourier transform infrared (FT-IR) spectrometry technique has been u...
Non-fickian moisture absorption in polymers coated with a thin nanocomposite layer
Altan, Altan; Altan, M. Cengiz; Guloglu, GÖRKEM EĞEMEN; Güloğlu, Görkem Eğemen (2014-01-01)
Moisture absorption in polymers and polymeric composites is well known to lead to significant degradation in mechanical properties. Most epoxy based composites may absorb 2 to 5 wt.% moisture when they are subjected to humid environments. Moisture absorption in polymers has been often characterized with Fickian or various non-Fickian models to describe the time-dependent absorption phenomena. Previous experiments have shown that dispersing moderate amounts of nanoclay in an epoxy resin can: (i) reduce the t...
Modelling and simulation of thin film semiconductor metal oxide gas sensor response
Atman, Berkan; Uludağ, Yusuf; Department of Chemical Engineering (2019)
Metal oxide based semiconductor gas sensors have attracted attention due to their superior properties. Over past five decades an extensive research had been conducted for understanding the true nature of the sensing mechanism, most suitable material and optimum operating conditions. SnO2 has received over years a great deal of attention as it can meet most of the necessary requirements of a gas sensor. Although commercially available gas sensors based on tin oxide are available and plenty of studies has bee...
Bactericidal and in vitro osteogenic activity of nano sized cobalt-doped silicate hydroxyapatite
Alshemary, Ammar Z.; Hussain, Rafaqat; Dalgic, Ali Deniz; Evis, Zafer (2022-10-01)
Hydroxyapatite (HA) particles with enhanced antibacterial properties can be prepared by integrating metal ions into the crystal structure of the nanoparticles. Cobalt and silicate ions containing HA (Co/Si-HA) with the formula Ca10-xCox(PO4)6-y(SiO4)y(OH)2 (x = 0.2, 0.6, and 1.0 and y = 0.5) was successfully synthesised by using microwave-assisted wet precipitation method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and inductively coupled...
Citation Formats
D. Vinichenko, M. G. Sensoy, C. M. Friend, and E. Kaxiras, “Accurate formation energies of charged defects in solids: A systematic approach,” PHYSICAL REVIEW B, pp. 0–0, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67562.