2003/07/29 by Veronique Le Floc'h, Véronique Le Floc’h, Floc'h, Veronique Le +7
Biochemistry, Genetics and Molecular Biology · Chemical Engineering · Physics and Astronomy · #Advanced Fluorescence Microscopy Techniques #Analytical Chemistry and Sensors #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Soft Condensed Matter (cond-mat.soft) #Spectroscopy and Quantum Chemical Studies #cond-mat.mtrl-sci #cond-mat.soft
paper · pdf · doi:10.48550/arxiv.cond-mat/0307708
submitted April 9th, 2003 to J. Phys. Chem. B
arxiv created 2003/07/29 · openalex publication_date 2003/07/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present high resolution two-photon excitation microscopy studies combining two-photon fluorescence (TPF) and second harmonic generation (SHG) in order to probe orientational distributions of molecular ensembles at room temperature. A detailed polarization analysis of TPF and SHG signals is used in order to unravel the parameters of the molecular orientational statistical distribution, using a technique which can be extended and generalized to a broad variety of molecular arrangements. A polymer film containing molecules active for TPF and/or SHG emission is studied as a model system. Polarized TPF is shown to provide information on specific properties pertaining to incoherent emission in molecular media, such as excitation transfer. SHG, being highly sensitive to a slight departure from centrosymmetry such as induced by an external electric field in the medium, complements TPF. The response of each signal to a variable excitation polarization allows investigation of molecular behavior in complex environments which affect their orientations and interactions.