Tags: ab initio

Resources (1-20 of 39)

  1. "Ab Initio" Theory of Novel Micro and Nanolasers

    19 May 2008 | | Contributor(s):: A. Douglas Stone

    While the laser is one of the most important inventions of the past century and one of the most interesting and controllable non-linear systems in physics, there is surprisingly little predictive theory of lasing properties. Predicting lasing thresholds and output power far above threshold in...

  2. ab initio Model for Mobility and Seebeck coefficient using Boltzmann Transport (aMoBT) equation

    11 Jun 2015 | | Contributor(s):: Alireza Faghaninia, Joel Ager (editor), Cynthia S Lo (editor)

    ab initio electronic transport model to calculate low-field electrical mobility and Seebeck coefficient of semiconductors in Boltzmann transport framework.

  3. ABINIT

    13 May 2004 | | Contributor(s):: Amritanshu Palaria, Xufeng Wang, Benjamin P Haley, Matteo Mannino, Gerhard Klimeck

    Run the community code ABINIT for electronic structure calculations under density functional theory through a convenient graphical user interface

  4. ABINIT: First-Time User Guide

    09 Jun 2009 | | Contributor(s):: Benjamin P Haley

    This first-time user guide provides an introduction to using ABINIT on nanoHUB. We include a very brief summary of Density Functional Theory along with a tour of the Rappture interface. We discuss the default simulation (what happens if you don't change any inputs, and just hit "simulate") as...

  5. BNC Annual Research Review: An Introduction to PRISM and MEMS Simulation

    04 Jun 2008 | | Contributor(s):: Jayathi Murthy

    This presentation is part of a collection of presentations describing the projects, people, and capabilities enhanced by research performed in the Birck Center, and a look at plans for the upcoming year.

  6. Calculating Resonances Using a Complex Absorbing Potential

    13 Mar 2008 | | Contributor(s):: Robin Santra

    The Siegert (or Gamow) wave function associated with a resonance state is exponentially divergent at large distances from the scattering target. A complex absorbing potential (CAP) provides a computationally simple and efficient technique for calculating the complex Siegert energy of a resonance...

  7. CNDO/INDO

    09 Oct 2007 | | Contributor(s):: Baudilio Tejerina, Jeff Reimers

    Semi-empirical Molecular Orbital calculations.

  8. Computational Chemistry: An Introduction to Molecular Dynamic Simulations

    08 Dec 2006 | | Contributor(s):: Shalayna Lair

    This module gives a brief overview of computational chemistry, a branch of chemistry concerned with theoretically determining properties of molecules. The fundamentals of how to conduct a computational project are discussed as well as the variety of different models that can be used. Because of...

  9. Computational Mathematics: Role, Impact, Challenges

    20 Dec 2007 | | Contributor(s):: Juan C. Meza

    This presentation was one of 13 presentations in the one-day forum, "Excellence in Computer Simulation," which brought together a broad set of experts to reflect on the future of computational science and engineering.

  10. Computational Nanoscience, Lecture 4: Geometry Optimization and Seeing What You're Doing

    13 Feb 2008 | | Contributor(s):: Jeffrey C Grossman, Elif Ertekin

    In this lecture, we discuss various methods for finding the ground state structure of a given system by minimizing its energy. Derivative and non-derivative methods are discussed, as well as the importance of the starting guess and how to find or generate good initial structures. We also briefly...

  11. Dynamics of Quantum Fluids: Path integral and Semiclassical Methods

    21 May 2008 | | Contributor(s):: Nancy Makri

    The interplay of many-body nonlinear interactions and quantum mechanical effects such as zero-point motion or identical particle exchange symmetries lead to intriguing phenomena in low-temperature fluids, some of which remain poorly understood. Recent advances in theory and methodology have...

  12. Dynamics on the Nanoscale: Time-domain ab initio studies of quantum dots, carbon nanotubes and molecule-semiconductor interfaces

    31 Jan 2008 | | Contributor(s):: Oleg Prezhdo

    Device miniaturization requires an understanding of the dynamical response of materials on the nanometer scale. A great deal of experimental and theoretical work has been devoted to characterizing the excitation, charge, spin, and vibrational dynamics in a variety of novel materials, including...

  13. Excellence in Computer Simulation: Computational Materials

    20 Dec 2007 | | Contributor(s):: Eric Schwegler

    This presentation was one of 13 presentations in the one-day forum, "Excellence in Computer Simulation," which brought together a broad set of experts to reflect on the future of computational science and engineering.

  14. Exploring Physical and Chemical control of molecular conductance: A computational study

    31 Jan 2008 | | Contributor(s):: Barry D. Dunietz

  15. Finite Size Scaling and Quantum Criticality

    02 Jan 2008 | | Contributor(s):: Sabre Kais

    In statistical mechanics, the finite size scaling method provides a systematic way to extrapolate information about criticality obtained from a finite system to the thermodynamic limit. For quantum systems, the finite size corresponds not to the spatial dimension but to the number of elements in...

  16. Finite Size Scaling and Quantum Criticality

    09 May 2007 | | Contributor(s):: Sabre Kais

    The study of quantum phase transitions, which are driven by quantum fluctuations as a consequence of Heisenberg's uncertainty principle, continues to be of increasing interest in the fields of condensed matter and atomic and molecular physics. In this field we have established an analogy between...

  17. IMA 2013 UQ: DFT-based Thermal Properties: Three Levels of Error Management

    02 Apr 2014 | | Contributor(s):: Kurt Lejaeghere

    It is often computationally expensive to predict finite-temperature properties of a crystal from density-functional theory (DFT). The temperature-dependent thermal expansion coefficient α, for example, is calculated from the phonon spectrum, and the melting temperature Tm can only be obtained...

  18. Large-scale first principles configuration interaction calculations of optical absorption in boron clusters

    07 Mar 2012 | | Contributor(s):: Ravindra L Shinde

    We have performed systematic large-scale all-electron correlated calculations on boron clustersBn (n=2–5), to study their linear optical absorption spectra. Several possible isomers of each clus-ter were considered, and their geometries were optimized at the coupled-cluster singles doubles(CCSD)...

  19. Lecture 4: The ab-initio Wigner Monte Carlo Method

    18 Nov 2014 | | Contributor(s):: Jean Michel D Sellier

    In this lecture, Dr. Sellier discusses the ab-initio Wigner Monte Carlo method for the simulation of strongly correlated systems.

  20. Matdcal

    30 Jan 2008 | | Contributor(s):: Kirk Bevan

    Non-equilibrium Green's Function Density Functional Theory Simulator