771577-73-2Relevant academic research and scientific papers
Two-photon absorption in three-dimensional chromophores based on [2.2]-paracyclophane
Bartholomew, Glenn P.,Rumi, Mariacristina,Pond, Stephanie J. K.,Perry, Joseph W.,Tretiak, Sergei,Bazan, Guillermo C.
, p. 11529 - 11542 (2004)
A series of α,ω-bis donor substituted oligophenylenevinylene dimers held together by the [2.2]-paracyclophane core were synthesized to probe how the number of repeat units and through-space delocalization influence two-photon absorption cross sections. Specifically, the paracyclophane molecules are tetra(4,7,12,15)-(4′-dihexylaminostyryl)[2.2]paracyclophane (3R D), tetra(4,7,12,15)-(4″-(4′-dihexylaminostyryl)styryl) [2.2]paracyclophane (5RD), and tetra(4,7,12,15)-(4?-(4″- (4′-dihexylaminostyryl)styryl)styryl)[2.2]paracyclophane (7RD). The compounds bis(1,4)-(4′-dihexylaminostyryl)benzene (3R) and bis(1,4)-(4″-(4′-dihexylaminostyryl)styryl)benzene (5R) were also synthesized to reveal the properties of the "monomeric" counterparts. The two-photon absorption cross sections were determined by the two-photon induced fluorescence method using both femtosecond and nanosecond pulsed lasers as excitation sources. While there is a red shift in the linear absorption spectra when going from the "monomer" chromophore to the paracyclophane "dimer" (i.e., 3R → 3RD, 5R → 5RD), there is no shift in the two-photon absorption maxima. A theoretical treatment of these trends and the dependence of transition dipole moments on molecular structure rely on calculations that interfaced time-dependent density functional theory (TDDFT) techniques with the collective electronic oscillator (CEO) program. These theoretical and experimental results indicate that intermolecular interactions can strongly affect Bu states but weakly perturb Ag states, due to the small dipole-dipole coupling between Ag states on the chromophores in the dimer.
Harnessing "click"-type chemistry for the preparation of novel electronic materials
Firstenberg, Michal,Shivananda, Kammasandra Nanjunda,Cohen, Irit,Solomeshch, Olga,Medvedev, Vladislav,Tessler, Nir,Eichen, Yoav
, p. 634 - 643 (2012/01/12)
Sequence-independent or "click"-type chemistry is applied for the preparation of novel π-conjugated oligomers. A variety of bi-functional monomers for Wittig-Horner olefination are developed and applied in a sequential protection-deprotection process for the preparation of structurally similar π-conjugated oligomers. Selected oligomers are incorporated as the organic semiconductors in light-emitting diodes and a field-effect transistor, demonstrating the potential of the approach. Sequence-independent or "click"-type chemistry is applied for the preparation of novel π-conjugated oligomers. A variety of bi-functional monomers for Wittig-Horner olefination are developed and applied in a sequential protection-deprotection process for the preparation of structurally similar π-conjugated oligomers. Selected oligomers are incorporated as the organic semiconductors in light-emitting diodes and a field-effect transistor, demonstrating the potential of the approach.
