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Synthesis , properties , and electrogenerated chemiluminescence ( ECL ) of a novel carbazole-based chromophore
| Content Provider | Semantic Scholar |
|---|---|
| Author | Wong, Kelvin Hung, Tien Chao, Teng-Chih Ho, Tin-Hung Rainbow. |
| Copyright Year | 2005 |
| Abstract | A novel molecule containing electron-rich carbazole and electron-deficient pyrimidine moieties exhibits useful and intriguing physical properties, including promising reversible redox behavior that gives rise to electrogenerated chemiluminescence (ECL). 2004 Elsevier Ltd. All rights reserved. Electrogenerated chemiluminescence (ECL) has widely been applied as a sensitive and selective detecting technique for many analytical applications; it is also an excellent model for investigating the mechanism of electron transfer. ECL is a process that involves photon generation by homogeneous electron transfer (ET) between electrochemically generated radical cations and radical anions that form in close proximity to the electrode surface in an ECL cell. Upon sweeping sequentially between negative and positive potentials over a short-time interval, the excited states of the electroactive species can be made to populate emitting states that subsequently relax to ground states with the emission of light of appropriate wavelengths. Both singlet and triplet states of the electroactive species can be formed depending on the annihilation enthalpy change (DHann) of the electron transfer reaction. The ion annihilation process can generate a singlet state (S-route) if the magnitude of DHann is larger than the energy needed to reach the excited singlet state (Es). On the other hand, if the value of DHann is lower than that of Es, but it is sufficient to generate the triplet state, then the electron transfer reaction will lead to the formation of that triplet state. It is still possible, however, to form a singlet state by triplet–triplet annihilation, which is a process known as the T-route. As a consequence, fluorescence is the normal emission from the electrochemically generated excited state of an electroactive species. For practical 0040-4039/$ see front matter 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.tetlet.2004.11.166 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://ntur.lib.ntu.edu.tw//bitstream/246246/170505/1/13.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Anions CCL21 gene CCL21 wt Allele Cations Chemiluminescence Electron tomography Excited state Exhibits as Topic Fluorescence Ions Large Photons Physical Phenomenon or Property Population Post-Traumatic Vegetative State Pyrimidines Sensor Singlet state Sweeping Triplet state carbazole respiratory electron transport chain process wavelength |
| Content Type | Text |
| Resource Type | Article |
