Theoretical Study on New Optical Functional Material by Unified Simulation Techniques

对相互作用近似（片段分子轨道理论：FMO）应用于发展量子化学；评价大分子体系光学性质的程序系统。引入了一种新的计算弱力的泛函，如范德华函数。此外，通过引入交换泛函的长范围校正，解决了长期存在的密度泛函理论用于评估大分子极化率的问题。利用FMO框架下的响应理论，对偶氮树状大分子的线性和非线性光学性质进行了非经验计算。在表示部分电荷转移的单位之间，发现了具有量子修正的简单加法规则。提出了量子和经典粒子外加剂溶剂化的统一密度泛函理论。该理论成功地应用于流体中过量电子的离域、聚合物链在超临界溶剂中的反常行为以及超临界流体中正电子湮灭率的显著增加等问题。

Pair interaction approximation (Fragment Molecular Orbital Theory:FMO) is applied for developing a quantum chemical ; program system for evaluating optical property of large molecular systems. A new functional for accounting weak force such as van der Waals is introduced Further a long standing problem of Density Functional Theory for evaluating polarizability of large molecules is resolved by introducing a long range correction in exchange functional. The non-empirical calculations are performed for evaluation of linear and non-linear optical properties of Azo-dendrimer using response theory within the FMO framework. Simple addition rule with a quantum correction between units representing partial charge transfer is found. A unified density functional theory for solvation is formulated for quantum and classical particle admixtures. The theory is successfully applied for the problems such as delocalization of excess electron in fluids, anomalous behavior of polymer chain in supercritical solvents and an remarkable increase of positron annihilation rate in supercritical fluid.