Tags: ab initio

Resources (21-39 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. Matdcal

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

    Non-equilibrium Green's Function Density Functional Theory Simulator

  3. UV/Vis Spectra simulator

    04 Mar 2008 | | Contributor(s):: Baudilio Tejerina

    This tool computes molecular electronic spectra.

  4. 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...

  5. CNDO/INDO

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

    Semi-empirical Molecular Orbital calculations.

  6. 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...

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

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

  8. 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...

  9. MIT Atomic-Scale Modeling Toolkit

    15 Jan 2008 | | Contributor(s):: daniel richards, Elif Ertekin, Jeffrey C Grossman, David Strubbe, Justin Riley

    Tools for Atomic-Scale Modeling

  10. 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...

  11. 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.

  12. Perspectives on Computational Quantum Chemistry

    20 Dec 2007 | | Contributor(s):: Martin P. Head-Gordon

    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.

  13. 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.

  14. MCW07 Electronic Level Alignment at Metal-Molecule Contacts with a GW Approach

    05 Sep 2007 | | Contributor(s):: Jeffrey B. Neaton

    Most recent theoretical studies of electron transport in single-molecule junctions rely on a Landauer approach, simplified to treat electron-electron interactions at a mean-field level within density functional theory (DFT). While this framework has proven relatively accurate for certain...

  15. MCW07 Modeling Charging-based Switching in Molecular Transport Junctions

    23 Aug 2007 | | Contributor(s):: Sina Yeganeh, , Mark Ratner

    We will discuss several proposed explanations for the switching and negative differential resistance behavior seen in some molecular junctions. It is shown that a proposed polaron model is successful in predicting both hysteresis and NDR behavior, and the model is elaborated with image charge...

  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. Renormalization Group Theories of Strongly Interacting Electronic Structure

    20 Apr 2007 | | Contributor(s):: Garnet Chan, NCN at Northwestern University

    Our work is in the area of the electronic structure and dynamics of complex processes. We engage in developing new and more powerful theoretical techniques which enable us to describe strong electronic correlation problems.Of particular theoretical interest are the construction of fast...

  18. 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...

  19. QC-Lab

    14 Feb 2006 | | Contributor(s):: Baudilio Tejerina

    Quantum Chemsitry Lab: Ab Initio and DFT molecular and electronic structure calculations of small molecules