Van Vooren Antoine, Lemaur Vincent, Ye Aijun, Beljonne David, Cornil Jérôme
Laboratory for Chemistry of Novel Materials, University of Mons-Hainaut, Place du Parc 20, B-7000 Mons, Belgium.
Chemphyschem. 2007 Jun 4;8(8):1240-9. doi: 10.1002/cphc.200700130.
We estimate, at a full quantum-chemical level, the various molecular parameters governing the rate of photoinduced charge generation and charge recombination in model organic structures containing a donor and an acceptor unit in view of the possible use of such systems in organic solar cells. The rate of through-space excitation dissociation, as predicted in the framework of the Marcus-Levich-Jortner theory, is found to be low in comparison to intramolecular decay processes when the donor and acceptor molecules are lying in a head-to-tail arrangement and high when the donor and acceptor molecules are superimposed in a cofacial arrangement. The charge separation rates for side-by-side donor-acceptor dyads are significantly increased by promoting through-bond interactions in covalently linked donor and acceptor units. This has motivated a detailed quantitative analysis of the influence of the nature, size, and conformation of the bridging moiety on the calculated transfer rates.
考虑到此类体系在有机太阳能电池中的潜在应用，我们在全量子化学水平上估算了控制含供体与受体单元的模型有机结构中光致电荷产生和电荷复合速率的各种分子参数。在马库斯 - 列维奇 - 约尔特纳理论框架下预测的空间穿越激发解离速率，当供体和受体分子呈头对尾排列时，与分子内衰变过程相比很低；而当供体和受体分子以共面排列叠加时则很高。通过促进共价连接的供体和受体单元中的键间相互作用，并排供体 - 受体二元体系的电荷分离速率显著提高。这促使我们对桥连部分的性质、大小和构象对计算出的转移速率的影响进行详细的定量分析。
