Transport of Excitation Energy in a Doped Molecular Aggregate. III. Numerical Investigation of Exciton Hopping with Various Exciton-Depleting Processes
A brute-force numerical investigation has been carried out on the hopping of excitons in a three-dimensional molecular aggregate. Possibilities of vibronic decay, rapid chemical reactions of saturated species, radiative decay of overpopulated molecules, and cooperative chemical reactions involving saturated exciton populations on traps of two different types have been considered. Investigations have been performed with two types of initial distribution of excitons-facial and random-and for 10000 or, sometimes, for 20000 time steps each of duration 1 ps. Several interesting observations have been made from this computer experiment: (1) The total number of occurrences of fast reactions depends upon the initial distribution of excitons. (2) It decreases if other exciton depleting processes are at work. (3) It also depends on the pattern of placement of traps. (4) The location of impurities also affects the rate of occurrence of these reactions. (5) The number of reactions need not necessarily increase with the number of reaction centers; in fact, it decreases as more centers are added when the supply of excitons is severely limited. (6) A complicated dynamics results when different types of additional processes, viz., enhanced fluorescence, radiative emissions, and cooperative chemical reactions are simultaneously allowed. The cooperative process has been clearly found to dominate. A first-order rate constant of about 10/sup 8/ s/sup -1/ has been claculated for the occurrence of the cooperative process. This rate is affected when other nonconserving processes are switched on. Observations (1), (4), and (5) are the most important conclusions of our work. They lie outside the scope of traditional models such as the random walk model, the diffusion model, and the lattice model for the migration of excitons in a molecular aggregate.
원문보기 무료다운로드 유료다운로드
- 원문이 없습니다.
유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.
NDSL에서는 해당 원문을 복사서비스하고 있습니다. 아래의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.