论文标题
使用Indeno [1,2-B]氟二聚体设计分子内单线叶片材料：DMRG和TDDFT研究
Designing intramolecular singlet-fission materials using indeno[1,2-b]fluorene dimers: A DMRG and TDDFT study
论文作者
论文摘要
使用或不使用苯垫片的Indeno [1,2-b]氟二聚体的低覆型激发态使用密度矩阵重新归一化组（DMRG）方法在Pariser-Parr-parple（PPP）模型Hamiltonian中计算。 DMRG计算表明，这里研究的所有二聚体都满足SF的基本能量条件。 SF是一个多人生成过程。允许旋转，该过程非常快。通过一次生成多个激子，SF低估了SQ极限，以提高单连接太阳能电池的光转换效率。通过密度功能理论（DFT）的边界轨道计算描述了三胞胎在共价间隔者两侧的轨道定位。支持纠缠的三胞胎 - 三个状态$^1（tt）$。这里的过程是分子内（ISF），它比分子间（XSF）过程具有许多优势，因为在分子间过程中，SF过程高度依赖于晶体包装，缺陷，位错等。但是，ISF不取决于晶体包装。我们的DMRG计算和TDDFT计算与文献中发现的实验结果非常吻合。因此，Indeno [1,2-B]氟均二聚体可以适用于ISF应用。
Low-lying excited states for indeno[1,2-b]fluorene homo dimers with or without benzene spacers are calculated using the Density Matrix Renormalization group (DMRG) approach within Pariser-Parr-Pople (PPP) model Hamiltonian. DMRG calculations suggest that all the dimers studied here satisfy the essential energy conditions for SF. SF is a multiexciton generation process. As it is spin allowed, the process is very fast. By generating multiple exciton at a time SF underestimate SQ limit to enhance photo-conversion efficiency of single junction solar cells. Frontier orbital calculation through Density Functional Theory (DFT) depicts orbital localization of triplets on either side of the covalent spacers. Which supports the entangled triplet-triplet state $^1(TT)$. Here the process is intramolecular (iSF), which has many advantages over the intermolecular (xSF) process, as in intermolecular process the SF process is highly dependent on the crystal packing, defects, dislocations etc. The entangled $^1(TT)$ state for xSF is localized on both of the chromophores, thus the appropriate crystal packing is essential for xSF. However iSF does not depend on the crystal packing. Our DMRG calculation and TDDFT calculation are in well agreement with experimental results found in the literature. Thus indeno[1,2-b]fluorene homo dimers can be applicable in iSF application.
