253878-42-1Relevant articles and documents
Synthesis and rare earth metal ion-sensing properties of aza-crown derivative incorporating with diaryl-1,3,4-oxadiazole
Yu, Tianzhi,Meng, Jing,Zhao, Yuling,Zhang, Hui,Han, Xiaoqian,Fan, Duowang
, p. 396 - 400 (2011/03/21)
A new fluorescent chemosensor (A18C6-Ox) in which a monoaza-18-crown-6 is linked to a diaryl-1,3,4-oxadiazole fluorophore by a methylene spacer has been synthesized to evaluate binding interaction with the rare earth ions by means of absorption and emission spectrophotometry. Absorption spectra of A18C6-Ox showed a broad band at 289 nm and there was no significant change in the presence of Sc3+, La3+, Pr3+, Sm3+, Gd3+, Tb3+, Yb3+ and Lu3+ except for Ce3+ and Eu3+. From the emission spectral change of A18C6-Ox, interaction of the rare earth ions with A18C6-Ox is very strong. The formation of A18C6-Ox complexing with Sc3+, La3+, Pr 3+, Sm3+, Gd3+, Tb3+, Yb 3+ and Lu3+ leads to an increase in fluorescence intensity of A18C6-Ox, while Ce3+ and Eu3+ ions interact strongly causing fluorescence quenching of A18C6-Ox. In addition, the optimal complexation stoichiometry of the rare earth ions with A18C6-Ox was investigated by the fluorescent titration.
Degenerate nonlinear absorption and optical power limiting properties of asymmetrically substituted stilbenoid chromophores
Lin, Tzu-Chau,He, Guang S.,Prasad, Paras N.,Tan, Loon-Seng
, p. 982 - 991 (2007/10/03)
Two-photon absorption (2PA) spectra (650-1000 nm) of a series of model chromophores were measured via a newly developed nonlinear absorption spectral technique based on a single and powerful femtosecond white-light continuum beam. The experimental results suggested that when either an electron-donor or an electron-acceptor was attached to a trans-stilbene at a para-position, an enhancement in molecular two-photon absorptivity was observed in both cases, particularly in the 650-800 nm region. However, the push-pull chromophores with both the donor and acceptor groups showed larger overall two-photon absorption cross-sections within the studied spectral region as compared to their mono-substituted analogues. The combined results of the solvent effect and the 1H-NMR studies indicated that stronger acceptors produce a more efficient intramolecular charge transfer character upon excitation, leading to increased molecular two-photon responses in this model-compound set. A fairly good 2PA based optical power limiting behavior from one of the model chromophores is also demonstrated.
A field-dependent organic LED consisting of two new high Tg blue light emitting organic layers: A possibility of attainment of a white light source
Cha, Soon Wook,Jin, Jung-Il
, p. 479 - 484 (2007/10/03)
Two new blue light emitting trimeric compounds of the Y-shape type having high glass transition temperatures were synthesized and EL behavior of LED devices consisting of bilayers of the two compounds was studied. One of the compounds is of hole-transporting type containing carbazole moieties, whereas the other is of electron-transporting type bearing phenyloxadiazole moieties. The bilayer LED devices exhibit a strong field-dependence and emit white light (simultaneous light-emittance in blue, green and red regions), at high applied electric fields. Increased interracial formation of exciplexes at stronger external fields appears to be responsible for this field-dependence.
Cooperative Enhancement of Two-Photon Absorption in Multi-branched Structures
Chung, Sung-Jae,Kim, Kyoung-Soo,Lin, Tzu-Chau,He, Guang S.,Swiatkiewicz, Jacek,Prasad, Paras N.
, p. 10741 - 10745 (2007/10/03)
Recent reports of molecular structures with considerably enhanced two-photon absorption cross-section have generated considerable interest in this phenomenon from both fundamental and applications perspectives. In this letter, we report cooperative enhanc