Designer Atoms: Engineering Rydberg Atoms Using Pulsed Electric Fields
20 Jun 2008 | Online Presentations | Contributor(s): F. Barry Dunning
Advances in experimental technique allow application of pulsed unidirectional electric fields, termed half-cycle pulses (HCPs), to Rydberg atoms whose characteristic times are much less than the classical electron orbital period. In this limit each HCP simply delivers an impulsive momentum...
Dynamics of Quantum Fluids: Path integral and Semiclassical Methods
21 May 2008 | Online Presentations | 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...
Selected Properties of Carbon Nanostructures: from Exotic Fullerenes to Nanotubes
30 Mar 2008 | Online Presentations | Contributor(s): Manfred M. Kappes
The talk presents results from ongoing projects in the field of carbonnanostructures: (i) Mass selected ion beam soft-landing has been usedto generate exotic fullerene materials comprising covalent linked,non-IPR cages. Apart from microscopic structure, we have studiedthermal and electronic...
Calculating Resonances Using a Complex Absorbing Potential
13 Mar 2008 | Online Presentations | 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...
Exploring Physical and Chemical control of molecular conductance: A computational study
31 Jan 2008 | Online Presentations | Contributor(s): Barry D. Dunietz
Dynamics on the Nanoscale: Time-domain ab initio studies of quantum dots, carbon nanotubes and molecule-semiconductor interfaces
31 Jan 2008 | Online Presentations | 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...
Orbital Mediated Tunneling in a New Unimolecular Rectifier
25 May 2007 | Online Presentations | Contributor(s): Robert Metzger, NCN SLC@Northwestern
In 1997 we showed that hexadecylquinolinium tricyanoquinodimethanide is a unimolecular rectifier, by scanning tunneling microscopy and also as a Langmuir-Blodgett (LB) monolayer, sandwiched between Al electrodes. We have now seen rectification in a new molecule: this rectification can be...
Renormalization Group Theories of Strongly Interacting Electronic Structure
20 Apr 2007 | Online Presentations | Contributor(s): Garnet Chan, NCN SLC@Northwestern
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...
Potassium Channels: Conduction, Selectivity, Blockage, Inactivation, and Gating
03 Nov 2006 | Online Presentations | Contributor(s): Benoit Roux, NCN SLC@Northwestern
The determination of the structure of the KcsA K+ channel fromStreptomyces lividan has made it possible to investigate the functionof a biological channel at the atomic level. Because of its structuralsimilarity with eukaryotic K-channels, investigations of KcsA areexpected to help understand a...
Exploring Electron Transfer with Density Functional Theory
11 Jun 2006 | Online Presentations | Contributor(s): Troy Van Voorhis
This talk will highlight several illustrative applications of constrained density functionaltheory (DFT) to electron transfer dynamics in electronic materials. The kinetics of thesereactions are commonly expressed in terms of well known Marcus parameters (drivingforce, reorganization energy and...