Direct experimental determination of spectral densities of molecular complexes

Abstract

Determining the spectral density of a molecular system immersed in a proteomic scaffold and in contact to a solvent is a fundamental challenge in the coarse-grained description of, e.g., electron and energy transfer dynamics. Once the spectral density is characterized, all the time scales are captured and no artificial separation between fast and slow processes need to be invoked. Based on the fluorescence Stokes shift function, we utilize a simple and robust strategy to extract the spectral density of a number of molecular complexes from available experimental data. Specifically, we show that experimental data for dye molecules in several solvents, amino acid proteins in water, and some photochemical systems (e.g., rhodopsin and green fluorescence proteins), are well described by a three-parameter family of sub-Ohmic spectral densities that are characterized by a fast initial Gaussian-like decay followed by a slow algebraic-like decay rate at long times.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 03, 2014
Source ID
10.1063/1.4900512

Entities

People

  • Leonardo A Pachón
  • Paul Brumer

Organizations

  • Air Force Office of Scientific Research
  • University of Antioquia
  • University of Toronto

Tags

Readers

  • Chemistry (specifically Chemical Fluorescence)
  • Molecular Genetics
  • Plasma Physics / Magnetohydrodynamics

Technology Areas

  • Biotechnology
  • Microelectronics