3.4k citations · 9.4k across the 28 of their papers we have counts for
28 papers
Probe Ferroelectricity by X-ray Absorption Spectroscopy in Molecular Crystal
Fujie Tang, Xuanyuan Jiang, Hsin-Yu Ko +8
We carry out X-ray absorption spectroscopy experiment at oxygen K-edge in croconic acid (C5H2O5) crystal as a prototype of ferroelectric organic molecular solid, whose electric pol…
Machine-Learning X-ray Absorption Spectra to Quantitative Accuracy
Matthew R. Carbone, Mehmet Topsakal, Deyu Lu +1
The advent of massive data repositories has propelled machine learning techniques to the front lines of many scientific fields, and exploring new frontiers by leveraging the predic…
Classification of Local Chemical Environments from X-ray Absorption Spectra using Supervised Machine Learning
Matthew R. Carbone, Shinjae Yoo, Mehmet Topsakal +1
X-ray absorption spectroscopy is a premier element-specific technique for materials characterization. Specifically, the x-ray absorption near-edge structure (XANES) encodes importa…
Decomposition of La2-xSrxCuO4 into Several La2O3 Phases at Elevated Temperatures in Ultra-High Vacuum inside a Transmission Electron Microscope
Jong Seok Jeong, Wangzhou Wu, Mehmet Topsakal +4
We report the decomposition of La2-xSrxCuO4 into La2O3 and Cu nanoparticles in ultra-high vacuum, observed by in-situ heating experiments in a transmission electron microscope (TEM…
Electronic structure of BaSnO3 investigated by high-energy-resolution electron energy-loss spectroscopy and ab initio calculations
Hwanhui Yun, Mehmet Topsakal, Abhinav Prakash +6
There has been growing interest in perovskite BaSnO3 due to its desirable properties for oxide electronic devices including high electron mobility at room temperature and optical t…
Evolutionary optimization of PAW data-sets for accurate high pressure simulations
Kanchan Sarkar, Mehmet Topsakal, N. A. W. Holzwarth +1
We examine the challenge of performing accurate electronic structure calculations at high pressures by comparing the results of all-electron full potential linearized augmented-pla…
A New Line Defect in NdTiO3 Perovskite
Jong Seok Jeong, Mehmet Topsakal, Peng Xu +3
Perovskite oxides form an eclectic class of materials owing to their structural flexibility in accommodating cations of different sizes and valences. They host well known point and…
First-principles study of crystal and electronic structure of rare-earth cobaltites
M. Topsakal, C. Leighton, R. M. Wentzcovitch
Using density functional theory plus self-consistent Hubbard (DFT) calculations, we have investigated the structural and electronic properties of the rare-earth cobalt…
Iron spin crossover and its influence on post-perovskite transitions in MgSiO and MgGeO
Gaurav Shukla, Mehmet Topsakal, Renata M. Wentzcovitch
MgGeO-perovskite is known to be a low-pressure analog of MgSiO-perovskite in many respects, but especially in regard to the post-perovskite transition. As such, investigati…
Accurate projected augmented wave (PAW) datasets for rare-earth elements (RE=La-Lu)
M. Topsakal, R. M. Wentzcovitch
We provide accurate projected augmented wave (PAW) datasets for rare-earth (RE) elements with some suggested Hubbard U values allowing efficient plane-wave calculations. Solid stat…
Frictional figures of merit for single layered nanostructures
S. Cahangirov, C. Ataca, M. Topsakal +2
We determined frictional figures of merit for a pair of layered honeycomb nanostructures, such as graphane, fluorographene, MoS and WO moving over each other, by carrying o…
Domain formation on oxidized graphene
M. Topsakal, S. Ciraci
Using first-principles calculations within density functional theory we demonstrate that the adsorption of single oxygen atom results in significant electron transfer from graphene…
Graphene coatings: An efficient protection from oxidation
M. Topsakal, H. Şahin, S. Ciraci
We demonstrate that graphene coating can provide an efficient protection from oxidation by posing a high energy barrier to the path of oxygen atom, which could have penetrated from…
Effects of static charging and exfoliation of layered crystals
M. Topsakal, S. Ciraci
Using first-principle plane wave method we investigate the effects of static charging on structural, elastic, electronic and magnetic properties of suspended, single layer graphene…
Structures of Fluorinated Graphenes and Their Signatures
Hasan Sahin, Mehmet Topsakal, Salim Ciraci
Recent synthesis of fluorinated graphene introduced interesting stable derivatives of graphene. In particular, fluorographene (CF), namely fully fluorinated chair conformation, is…
Static charging of graphene and graphite slabs
Mehmet Topsakal, Salim Ciraci
The effect of external static charging of graphene and its flakes are investigated by using first-principles calculations. While the Fermi level of negatively charged graphene rise…
Long ranged interactions in carbon atomic chains
S. Cahangirov, M. Topsakal, S. Ciraci
Based on first-principles calculations we revealed fundamental properties of infinite and finite size monatomic chains of carbon atoms in equilibrium and under an applied strain. D…
Current-voltage (I-V) characteristics of armchair graphene nanoribbons under uniaxial strain
Mehmet Topsakal, V. M. Kemal Bagci, Salim Ciraci
The current-voltage (I-V) characteristics of armchair graphene nanoribbons under a local uniaxial tension are investigated by using first principles quantum transport calculations.…
A First-Principles Study of Defects and Adatoms in Silicon Carbide Honeycomb Structures
E. Bekaroglu, M. Topsakal, S. Cahangirov +1
We present a study of mechanical, electronic and magnetic properties of two dimensional (2D), monolayer of silicon carbide (SiC) in honeycomb structure and its quasi 1D armchair na…
Armchair nanoribbons of silicon and germanium honeycomb structures
S. Cahangirov, M. Topsakal, S. Ciraci
We present a first-principles study of bare and hydrogen passivated armchair nanoribbons of the puckered single layer honeycomb structures of silicon and germanium. Our study inclu…
The response of mechanical and electronic properties of graphane to the elastic strain
M. Topsakal, S. Cahangirov, S. Ciraci
Based on first-principles calculations, we resent a method to reveal the elastic properties of recently synthesized monolayer hydrocarbon, graphane. The in-plane stiffness and Pois…
Monolayer honeycomb structures of group IV elements and III-V binary compounds
Hasan Sahin, S. Cahangirov, M. Topsakal +4
Using first-principles plane wave calculations, we investigate two dimensional honeycomb structure of Group IV elements and their binary compounds, as well as the compounds of Grou…
A First-Principles Study of Zinc Oxide Honeycomb Structures
M. Topsakal, S. Cahangirov, E. Bekaroglu +1
We present a first-principles study of the atomic, electronic, and magnetic properties of two-dimensional (2D), single and bilayer ZnO in honeycomb structure and its armchair and z…
Elastic and plastic deformation of graphene, silicene, and boron nitride honeycomb nanoribbons under uniaxial tension: A first-principles density-functional theory study
Mehmet Topsakal, Salim Ciraci
This study of elastic and plastic deformation of graphene, silicene, and boron nitride (BN) honeycomb nanoribbons under uniaxial tension determines their elastic constants and reve…