title: Probing chirality fluctuations in molecules by nonlinear optical spectroscopy.
abstract: Symmetry breaking caused by geometric fluctuations can enable processes that are otherwise forbidden. An example is a perylene bisimide dyad whose dipole moments are perpendicular to each other. Förster-type energy transfer is thus forbidden at the equilibrium geometry since the dipolar coupling vanishes. Yet, fluctuations of the geometric arrangement have been shown to induce finite energy transfer that depends on the dipole variance, rather than the mean. We demonstrate an analogous effect associated with chirality symmetry breaking. In its equilibrium geometry, this dimer is non-chiral. The linear chiral response which depends on the average geometry thus vanishes. However, we show that certain 2D chiral optical signals are finite due to geometric fluctuations. Furthermore, the correlation time of these fluctuations can be experimentally revealed by the waiting time dependence of the 2D signal.
authors.affiliation: I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Mann
authors.affiliation: I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Nalbach
authors.affiliation: Department of Chemistry, University of California, Irvine, California 92697-2025, USA.
authors.forename: S
authors.initials: S
authors.lastname: Mukamel
authors.affiliation: I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Thorwart
mesh_terms: D004735:Energy Transfer; D007094:Imides / Q000737:chemistry*; D017711:Nonlinear Dynamics; D055620:Optical Phenomena; D010569:Perylene / Q000031:analogs & derivatives* / Q000737:chemistry; D013057:Spectrum Analysis; D013237:Stereoisomerism
chemical_list: D007094:Imides; C510697:perylene bisimide; D010569:Perylene