Electronic and structural properties of surfaces and interfaces
EMSL Project ID
9790
Abstract
This research is aimed at understanding the roles that surfaces and interfaces have on the properties of materials. Primarily, this work is separated into two areas: calculations of semiconductor surfaces, clusters and metal-semiconductor interfaces, and calculations of bulk interfaces such as twin boundaries and grain boundaries. Most of the computational work on semiconductor surfaces and metal-semiconductor interfaces will be carried out in collaboration with the experimental group (Tringides's group) at Ames laboratory. The second area is in collaboration with Man Yoo and Chong-Long Fu at Oak Ridge National Laboratory.Our specific goals are as follows:
(a) To perform tight-binding molecular dynamics simulations and ab initio calculations to study the atomistic geometry and electronic properties of transition-metal-silicon structures (i.e., ring clusters) at Si surfaces.
(b) To perform ab initio calculations and tight-binding molecular dynamics simulations to study the stability, atomic structure, and electronic properties of clean and hydrogen- or oxygen-terminated silicon nanowire surface and nanoclusters.
(c) To perform tight-binding and ab initio electronic structure and total energy calculations of Pb-covered silicon surfaces and Pb/Si interfaces (e.g., Pb/Si(111) and Pb/Si(100)) to understand the growth mechanism of nanoscale Pb islands and wires on silicon surfaces.
(d) To perform our tight-binding molecular dynamics and ab initio molecular dynamics calculations and simulations to study the binding, diffusion and dynamics of Si and Ge on flat and stepped Si(001) surface.
(e) To perform our classical and tight-binding study of grain boundaries in Si to better understand the energetics of the symmetric tilt grain boundaries.
(f) To develop effective genetic algorithm searches for optimizing grain boundary structures and silicon nanowire surfaces.
(g) To calculate the energies and structures of twin boundaries in the hcp metals Mg, Ti and Zr, using both classical and ab initio approaches.
(h) To perform our tight-binding calculations of screw dislocation in Mo in order to understand the core structure and the mechanisms of motion of the dislocation cores in this material.
Project Details
Project type
Exploratory Research
Start Date
2004-07-14
End Date
2005-12-15
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
: Andzelm J, BC Rinderspacher, AM Rawlett, J Dougherty, R Baer, and N Govind. 2009. "Performance of DFT Methods in the Calculation of Optical Spectra of TCF-Chromophores." Journal of Chemical Theory and Computation 5(10):2835-2846. doi:10.1021/ct900231r
Electronic and structural properties of surfaces and interfaces
Govind N, PV Sushko, WP Hess, M Valiev, and K Kowalski. 2009. "Excitons in Potassium Bromide: A Study using Embedded Time-dependent Density Functional Theory and Equation-of-Motion Coupled Cluster Methods." Chemical Physics Letters 470(4-6):353-357. doi:10.1016/j.cplett.2009.01.073
Jensen L, and N Govind. 2009. "Excited States of DNA Base Pairs Using Long-Range Corrected Time-Dependent Density Functional Theory." Journal of Physical Chemistry A 113(36):9761-9765.
Shluger AL, KP Mckenna, PV Sushko, DM Ramo, and AV Kimmel. 2009. "Modelling of electron and hole trapping in oxides." Modelling and Simulation in Materials Science and Engineering 17(084004):21. doi:10.1088/0965-0393/17/8/084004