A layered red-emitting chromophoric organic salt

作者：Yi Chenyi; Blum Carmen; Liu Shi Xia^*; Ran Ying Fen; Frei Gabriela; Neels Antonia; Stoeckli Evans Helen; Calzaferri Gion; Leutwyler Samuel; Decurtins Silvio

来源：Crystal Growth & Design, 2008, 8(8): 3004-3009.

DOI：10.1021/cg800122v

We have investigated a synthetic route as well as the molecular assembly and the optical properties of a novel,pi-conjugated system, namely, the anion (E)-3-(3-amino-2,4-dicyanophenyl)-1,1-dicyanoprop-2-en-1-ide, in the form of its tetrabutylammonium salt (1). Through the combined actions of directional hydrogen bonds and Coulombic interactions, a two-dimensional molecular topology is realized whereby the extended monolayers of the strongly chromophoric g-conjugated anions are spatially isolated by the tetrabutylammonium cations. The chromophoric properties of the anion originate from very intense low-energy pi-pi* absorptions, with a high oscillator strength, f(exp) = 0.84 at 468 nm. Further characteristic features are a S-1 -> S-0 fluorescence emission not only in solution but also in the solid state at room temperature. The remarkable type of organization of the organic chromophores into a solid state sheet structure suppresses a possible quenching of a solid state emission and, quite interestingly, allows in principle probing of the photoexcited exciton states based on a defined molecular geometry.

• 出版日期2008-8