title: Probing environment fluctuations by two-dimensional electronic spectroscopy of molecular systems at temperatures below 5 K.
abstract: Two-dimensional (2D) electronic spectroscopy at cryogenic and room temperatures reveals excitation energy relaxation and transport, as well as vibrational dynamics, in molecular systems. These phenomena are related to the spectral densities of nuclear degrees of freedom, which are directly accessible by means of hole burning and fluorescence line narrowing approaches at low temperatures (few K). The 2D spectroscopy, in principle, should reveal more details about the fluctuating environment than the 1D approaches due to peak extension into extra dimension. By studying the spectral line shapes of a dimeric aggregate at low temperature, we demonstrate that 2D spectra have the potential to reveal the fluctuation spectral densities for different electronic states, the interstate correlation of static disorder and, finally, the time scales of spectral diffusion with high resolution.
authors.affiliation: Department of Theoretical Physics, Vilnius University, Sauletekio al 9-III, 10222 Vilnius, Lithuania.
authors.forename: Olga
authors.initials: O
authors.lastname: Rancova
authors.affiliation: Department of Chemistry and Department of Physics, Kansas State University, 213 CBC Building Manhattan, Kansas 66506-0401, USA.
authors.forename: Ryszard
authors.initials: R
authors.lastname: Jankowiak
authors.affiliation: Department of Theoretical Physics, Vilnius University, Sauletekio al 9-III, 10222 Vilnius, Lithuania.
authors.forename: Darius
authors.initials: D
authors.lastname: Abramavicius
mesh_terms: D004583:Electrons; D005453:Fluorescence; D013057:Spectrum Analysis; D013696:Temperature