We have designed A-D-π-D-A type three new small molecular donor materials denoted as FD-IND, FD-DCV and FD-NBR, which have been synthesised and their photo-physical, electrochemical and thermal properties explored. The synthesised materials have fluorene as “π-spacer,” dithieonopyrrole as “Donor” (D) and various “Acceptor” (A) units are 1,3-indanedione (IND), dicyanovinylene (DCV) and N-butyl rhodanine (NBR). All these three materials have good solubility (~30 mg/mL) in most common organic solvents and have relatively broad absorption in the visible region covering the range of 300-650 nm with two primary absorption bands. The absorption bands located at shorter wavelength region are ascribed to a localized aromatic π-π* transition of the A-D-π-D-A system, while the bands at longer wavelength are mainly attributed to an ICT transition. All the compounds exhibit excellent thermal stabilities in the range of 260-373°C. Cyclic voltammetry data provided HOMO values as −5.26, −5.32 and −5.32 eV for FD-NBR, FD-DCV and FD-IND respectively. LUMO values estimated from HOMO values and optical band gap are −3.27, −3.22 and −3.37 eV for FD-NBR, FD-DCV and FD-IND respectively. Therefore, these are potential molecules for organic solar cells.

中文翻译：

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封端受体影响AD-π-DA型小分子电子供体光物理，电化学和热学参数的实验研究

我们已经设计了AD-π-DA型三种新型小分子供体材料，分别表示为FD-IND，FD-DCV和FD-NBR已合成，并探索了它们的光物理，电化学和热性能。合成材料的芴为“π-间隔基”，二硫杂吡咯为“供体”（D），各种“受体”（A）单元为1,3-茚满二酮（IND），二氰基亚乙烯基（DCV）和N-丁基若丹宁（NBR） ）。所有这三种材料在大多数常见有机溶剂中均具有良好的溶解度（〜30 mg / mL），并且在可见范围内具有两个吸收峰的相对较宽的吸收范围为300-650 nm。位于较短波长区域的吸收带归因于AD-π-DA系统的局部芳香族π-π*跃迁，而较长波长的吸收带主要归因于ICT跃迁。所有化合物均在260-373°C的温度范围内表现出出色的热稳定性。FD-NBR，FD-DCV和FD-IND。从HOMO值和光学带隙估计的LUMO值对于FD-NBR，FD-DCV和FD-IND分别为-3.27，-3.22和-3.37eV 。因此，这些是有机太阳能电池的潜在分子。