Hadi Hayder M
Department of Medical Physics, College of Science, University of Al-Qadisiyah, Al-Diwaniya, Iraq.
J Mol Model. 2025 Mar 17;31(4):115. doi: 10.1007/s00894-025-06347-2.
This study analyzed the electronic and optical properties of pentacene derivatives chemically modified by adding nitro and amine groups at different positions on the molecular structure. The study aimed to understand the impact of these modifications on electronic and optical applications, focusing on improving performance in organic electronic devices and solar cells. The results showed that adding nitro groups as electron acceptors and amine groups as electron donors reduces the energy gap and increases the chemical activity of the molecules. It was also observed that changing the positions of these groups significantly affects the polar moment, reflecting changes in the charge distribution within the molecules. In terms of optical properties, the modified molecules showed high light absorption in the visible region of the electromagnetic spectrum, making them promising candidates for organic solar cell applications, where high light absorption efficiency is a prerequisite for these applications.
All calculations were performed using the Gaussian 09 software package. The study included molecular geometry optimization using density functional theory (DFT) with the B3LYP hybrid functional and 6-31G(d,p) basis set. Electronic properties, such as the highest occupied molecular orbital HOMO and lowest unoccupied molecular orbital LUMO energy levels, and the energy gap between them were calculated to evaluate the stability and chemical activity. Time-dependent density functional theory (TD-DFT) was used to analyze the optical properties and light absorption. In addition, fixed points were confirmed by vibrational frequency analysis to ensure that the optimized molecular structures represent stable states. The study also included a polar moment calculation to evaluate the effect of chemical modifications on the polarity of the molecules.
本研究分析了在并五苯衍生物分子结构的不同位置添加硝基和胺基进行化学修饰后的电子和光学性质。该研究旨在了解这些修饰对电子和光学应用的影响，重点是提高有机电子器件和太阳能电池的性能。结果表明，添加作为电子受体的硝基和作为电子供体的胺基会减小能隙并增加分子的化学活性。还观察到改变这些基团的位置会显著影响极矩，反映出分子内电荷分布的变化。在光学性质方面，修饰后的分子在电磁光谱的可见光区域表现出高吸光率，这使其成为有机太阳能电池应用的有前途的候选材料，因为高吸光效率是这些应用的先决条件。
所有计算均使用高斯09软件包进行。该研究包括使用密度泛函理论（DFT）和B3LYP杂化泛函以及6-31G(d,p)基组进行分子几何结构优化。计算了最高占据分子轨道HOMO和最低未占据分子轨道LUMO能级等电子性质以及它们之间的能隙，以评估稳定性和化学活性。使用含时密度泛函理论（TD-DFT）分析光学性质和光吸收。此外，通过振动频率分析确认固定点，以确保优化后的分子结构代表稳定状态。该研究还包括极矩计算，以评估化学修饰对分子极性的影响。
