Accession Number : ADA473839


Title :   Insight into the Nonlinear Absorbance of Two Related Series of Two-Photon Absorbing Chromophores (Postprint)


Descriptive Note : Journal article


Corporate Author : UES INC DAYTON OH


Personal Author(s) : Jakubiak, Rachel ; Tan, Loon-Seng ; Fleitz, Paul A. ; Pachter, Ruth ; Rogers, Joy E. ; Slagle, Jonathan E. ; McLean, Daniel G. ; Sutherland, Richard L. ; Brant, Mark C. ; Heinrichs, James ; Kannan, Ramamurthi


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA473839


Report Date : 2007


Pagination or Media Count : 11


Abstract : A comprehensive photophysical study of the linear and nonlinear absorption properties has been carried out on two series of two-photon absorbing dyes to gain insight into how structure-property relationships influence observed nonlinear absorption. The materials studied consist of an electron accepting benzothiazole group connected to an electron donating diphenylamine via a fluorene bridging group. Two series differ from each other by the addition of one phenyl group and for each series one-arm (dipolar, AF240 and AF270), two-arm (quadrupolar, AF287 and AF295), and three-arm (octupolar, AF350 and AF380) versions were studied. Overall the AF240 series exhibits higher intrinsic two-photon absorption (TPA) cross-sections than the AF270 series as well as enhanced nanosecond nonlinear absorption, with an increase with number of branches. The enhanced nanosecond nonlinearity is understood by taking into account the contribution from the singlet and triplet excited states and was verified by a two-photon assisted excited-state absorption model that satisfactorily predicts the nonlinear absorption of the chromophores.


Descriptors :   *CHROMOPHORES , *NONLINEAR SYSTEMS , *TWO PHOTON ABSORPTION , PHYSICAL PROPERTIES , ABSORPTION , BRIDGES , FLUORENES , PHENYLAMINES , PHENYL RADICALS , DYES , ABSORBERS(MATERIALS) , MOLECULAR STRUCTURE


Subject Categories : ORGANIC CHEMISTRY
      OPERATIONS RESEARCH
      ATOMIC AND MOLECULAR PHYSICS AND SPECTROSCOPY


Distribution Statement : APPROVED FOR PUBLIC RELEASE