@article{areshkin_shenderova_schall_brenner_2005, title={Self-consistent tight binding model adapted for hydrocarbon systems}, volume={31}, ISSN={["1029-0435"]}, DOI={10.1080/08927020500044988}, abstractNote={A self-consistent environment-dependent tight binding method is presented that was developed to simulate eigenvalue spectra, electron densities and Coulomb potential distributions for hydrocarbon systems. The method builds on a non-self-consistent environment-dependent tight binding model for carbon [Tang et al., Phys. Rev. B 53, 979 (1996)] with parameters added to describe hydrocarbon bonds and to account for self-consistent charge transfer. A detailed description of the parameterization procedure is given. Case studies that examine electron emission-related properties of carbon nanotubes demonstrate the utility of the method. The results of these calculations indicate that field enhancement in the vicinity of a nanotube tip is higher for open-ended than for capped nanotubes. At the same time open-ended nanotubes exhibit a higher potential barrier in the tip region. This barrier deteriorates the coupling between conducting states in the nanotube and free electron states in vacuum, and may increase the field emission threshold.}, number={8}, journal={MOLECULAR SIMULATION}, author={Areshkin, DA and Shenderova, OA and Schall, JD and Brenner, DW}, year={2005}, month={Jul}, pages={585–595} }
@article{areshkin_shenderova_schall_adiga_brenner_2004, title={A self-consistent tight binding model for hydrocarbon systems: application to quantum transport simulation}, volume={16}, ISSN={["1361-648X"]}, DOI={10.1088/0953-8984/16/39/018}, abstractNote={A self-consistent environment-dependent (SC-ED) tight binding (TB) method for hydrocarbons that was developed for quantum transport simulations is presented. The method builds on a non-self-consistent environment-dependent TB model for carbon (Tang et al 1996 Phys. Rev. B 53 979) with parameters added to describe hydrocarbon bonds and to account for self-consistent charge transfer. The SC-EDTB model assumes an orthogonal basis set. Orthogonality is a key element for adapting the SC-EDTB scheme to transport problems because it substantially increases the efficiency of the Newton–Raphson algorithm used to accelerate self-consistency convergence under non-equilibrium conditions. Compared to most existing TB schemes the SC-EDTB scheme is distinctive in two respects. First, self-consistency is added through the exact evaluation of Hartree and linear expansion of exchange integrals. All Hamiltonian elements belonging to the same atom are affected by charge transfer, not just the diagonal elements. The second distinction is the choice of SC-EDTB parameters; they were fitted to Mulliken populations and eigenvalue spectra rather than energies or elastic properties. The former are directly related to the conductivity and potential profile, which are essential for transport simulation. No two-centre repulsive term parametrization was performed. The functionality of the method is exemplified by computing I–V curves, non-equilibrium potential profiles and current density for a resonant tunnelling device.}, number={39}, journal={JOURNAL OF PHYSICS-CONDENSED MATTER}, author={Areshkin, DA and Shenderova, OA and Schall, JD and Adiga, SP and Brenner, DW}, year={2004}, month={Oct}, pages={6851–6866} }
@article{zhirnov_shenderova_jaeger_tyler_areshkin_brenner_hren_2004, title={Electron emission properties of detonation nanodiamonds}, volume={46}, ISSN={["1063-7834"]}, DOI={10.1134/1.1711444}, number={4}, journal={PHYSICS OF THE SOLID STATE}, author={Zhirnov, VV and Shenderova, OA and Jaeger, DL and Tyler, T and Areshkin, DA and Brenner, DW and Hren, JJ}, year={2004}, pages={657–661} }
@article{areshkin_shenderova_adiga_brenner_2004, title={Electronic properties of diamond clusters: self-consistent tight binding simulation}, volume={13}, ISSN={["1879-0062"]}, DOI={10.1016/j.diamond.2004.04.012}, abstractNote={A self-consistent environment-dependent tight binding method is used to examine electron emission-related properties of hydrogen passivated nano-diamond (ND) particles. For sizes larger than 2.5 nm particle bandgap was found to be equal to the bandgap of bulk diamond. Coulomb potential distributions and electron affinities of clusters were found to be insensitive to the particle size if it exceeds 1.0 nm. Tunneling probabilities for homogeneous and inhomogeneous emission models were estimated. The simulation results indicate that the low emission threshold for hydrogen passivated diamond nano-clusters is due to hydrogen-assisted emission from the edges of small unpassivated islands. Essentially the same mechanism is claimed to be responsible for good emission properties of hydrogen passivated diamond films by Ristein [Diam. Relat. Mater. 9, 1129 (2000)].}, number={10}, journal={DIAMOND AND RELATED MATERIALS}, author={Areshkin, DA and Shenderova, OA and Adiga, SP and Brenner, DW}, year={2004}, month={Oct}, pages={1826–1833} }
@article{shenderova_areshkin_brenner_2003, title={Bonding and stability of hybrid diamond/nanotube structures}, volume={29}, ISSN={["1029-0435"]}, DOI={10.1080/0892702021000049691}, abstractNote={Geometrical considerations combined with detailed atomic modeling are used to define general classes of diamond/carbon nanotube interface structures with low residual stresses and no unsatisfied bonding. Chemically and mechanically robust interfaces are predicted, supporting recent experimental studies in which structures of this type were proposed.}, number={4}, journal={MOLECULAR SIMULATION}, author={Shenderova, OA and Areshkin, D and Brenner, DW}, year={2003}, month={Apr}, pages={259–268} }
@article{areshkin_shenderova_schall_brenner_2003, title={Convergence acceleration scheme for self-consistent orthogonal-basis-set electronic structure methods}, volume={29}, ISSN={["1029-0435"]}, DOI={10.1080/0892702031000092197}, abstractNote={A new self-consistent convergence acceleration scheme that is a variant of the Newton-Raphson algorithm for non-linear systems of equations is presented. With this scheme, which is designed for use with minimal orthogonal basis set electronic structure methods, the conventional Newton-Raphson scaling with respect to the number of atoms is enhanced from quartic to cubic. The scheme is demonstrated using a self-consistent environment-dependent tight binding model for hydrocarbons that allows an efficient and reasonably precise simulation of charge density distortions due to external electric fields, finite system sizes, and surface effects. In the case of a metallic system, self-consistency convergence starts at a high fictitious temperature, typically 1500 K. As the electron density approaches the self-consistent configuration the temperature is decreased. Typically, seven to nine iterations are required to achieve self-consistency in metallic systems to a final temperature of 300 K. For systems with a finite band gap the convergence may start at the target temperature so that temperature reduction is unnecessary, and typically two iterations are needed to achieve self-consistency. The convergence algorithm can handle extremely high applied fields and is very robust with respect to initial electron densities.}, number={4}, journal={MOLECULAR SIMULATION}, author={Areshkin, DA and Shenderova, OA and Schall, JD and Brenner, DW}, year={2003}, month={Apr}, pages={269–286} }
@article{brenner_shenderova_areshkin_schall_frankland_2002, title={Atomic modeling of carbon-based nanostructures as a tool for developing new materials and technologies}, volume={3}, number={5}, journal={Computer Modeling in Engineering & Sciences : CMES}, author={Brenner, D. W. and Shenderova, O. A. and Areshkin, D. A. and Schall, J. D. and Frankland, S. J. V.}, year={2002}, pages={643–673} }
@article{shenderova_lawson_areshkin_brenner_2001, title={Predicted structure and electronic properties of individual carbon nanocones and nanostructures assembled from nanocones}, volume={12}, ISSN={["1361-6528"]}, DOI={10.1088/0957-4484/12/3/302}, abstractNote={Calculations using an analytic potential show that carbon nanocones can exhibit conventional cone shapes or can form concentric wave-like metastable structures, depending on the nanocone radius. Single nanocones can be assembled into extended two-dimensional structures arranged in a self-similar fashion with fivefold symmetry as system size is increased. Calculations of the electronic properties of nanocones indicate that a pentagon in the centre of a cone is the most probable spot for emitting tunnelling electrons in the presence of an external field. This implies that nanocone assemblies, if practically accessible, could be used as highly localized electron sources for templating at scales below more traditional lithographies.}, number={3}, journal={NANOTECHNOLOGY}, author={Shenderova, OA and Lawson, BL and Areshkin, D and Brenner, DW}, year={2001}, month={Sep}, pages={191–197} }