Hirata, Shuzo; Hara, Hyuman; Bhattacharjee, Indranil published the artcile< Phosphorescence Quenching of Heavy-Atom-Free Dopant Chromophores Triggered by Thermally Activated Triplet Exciton Diffusion of a Conjugated Crystalline Host>, Formula: C44H40P2, the main research area is phosphorescence quenching heavy atom dopant chromophore thermally activated triplet.
Persistent room-temperature phosphorescence (pRTP) from aggregated mol. crystalline materials is important for stable high-resolution afterglow imaging. However, an unclear understanding concerning the deactivation mechanism from the lowest triplet excited state (T1) precludes the development of highly efficient pRTP. Here, we report the reasons for the presence and absence of pRTP from a heavy-atom-free conjugated dopant in heavy-atom-free conjugated mol. crystals. N,N-di(9H-fluoren-2-yl)phenanthrene-3-amine (DFAP) was sep. doped into fluorene crystals and (S)-2,2′-bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene ((S)-H8-BINAP) crystals. DFAP doped in fluorene crystals with stronger intermol. interactions did not generate RTP, while DFAP doped in (S)-H8-BINAP crystals with weaker intermol. interactions showed strong pRTP. The pRTP of DFAP doped in (S)-H8-BINAP crystals is explained by the deep confinement of the T1 of DFAP in the (S)-H8-BINAP crystals with a large T1 energy. The absence of RTP from DFAP doped in fluorene crystals is explained by the temperature dependence of phosphorescence and quantum calculations, which suggest that deactivation is mainly caused by quenching after diffusion of triplet excitons of the host crystals. The temperature dependence of the triplet-triplet annihilation-based delayed fluorescence of the fluorene crystalline host confirms that the triplet diffusion of the fluorene crystalline host deactivates the triplet excitons of DFAP.
Journal of Physical Chemistry C published new progress about Chromophores. 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Formula: C44H40P2.
Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate