Linear and Two-Photon Photophysical Properties of a Series of Symmetrical Diphenylaminofluorenes

• Published in: Chemistry of materials Vol. 16; no. 11; pp. 2267 - 2273
• Main Authors: Belfield, Kevin D, Morales, Alma R, Hales, Joel M, Hagan, David J, Van Stryland, Eric W, Chapela, Victor M, Percino, Judith
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.06.2004
• Subjects: Applied sciences; Chemistry; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; General and physical chemistry; Physicochemistry of polymers; Physics; Polymers; Inorganic compounds; Organic compounds
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm035253g

A series of linear, symmetrical, diphenylaminofluorene-based materials are reported. The series investigated was model 9,9-didecyl-2,7-bis(N,N-diphenylamino)fluorene (1), oligomer 9,9-didecyl-N,N-bis(9,9-didecyl-7-N,N-diphenylaminofluoren-2-yl)-N, N-diphenyl-fluorene-2,7-diamine (2), and poly(9,9-didecyl-2,7-diphenylaminofluorene) (3). Structural characterization and photophysical properties, including linear absorption, quantum yields, single photon fluorescence, and two-photon absorption (2PA) spectra, were studied in polar and nonpolar solvents. 2PA spectra were determined by two independent methods:  a nonlinear transmission method employing a femtosecond white-light continuum (WLC) and a two-photon fluorescence (2PF) method. Polymer 3, a low-molecular-weight polymer with fourteen fluorene units, exhibited a very large two-photon absorption cross-section of 17 200 and 6800 × 10-50 cm4 s photon-1 molecule-1 as estimated from the WLC and 2PF methods, respectively.