2021-01-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/672284"該項目旨在對周期性系統的物理和化學性質進行第一個原理研究。具體目標可能如下： 1.週期系統振動譜的第一性原理模擬研究 2.週期系統電子激勵的時變泛函理論方法 3.用於結晶有機半導體導熱的密度泛函微擾理論方法。 1.基於分子的周期性材料的拉曼和太赫茲振動光譜學引起了實驗光譜學組和第一性原理模擬組的關注。週期性材料（例如聚合物，有機-無機雜化鈣鈦礦（OIHPs）和金屬有機框架（MOFs））的振動光譜學可提供有關堆疊構型（聚合物，OIHPs）的信息的原子級信息，（OHIPs， MOFs）。這樣的原子級信息對於理解“分子參數”與基於分子的材料的物理和化學功能之間的關係非常重要。該主題的主要科學目標之一是建立上述材料的光譜特徵與幾何結構之間的關係。 2.週期系統電子激勵的理論預測仍然頗具挑戰性，因為大多數基於多體格林函數（例如GW / BSE（Bethe-Salpeter方程））的精確理論方法都需要相當高的計算資源，即使對於簡單系統，例如石墨烯。具體目標將是隨時間變化的密度泛函理論（TD-DFT），其研究（i）聚合物側基的取代如何影響光學響應，以及（ii）兩種類型的聚合物的偶聯如何影響聚合物的光學響應。電子激勵。將闡明堆疊結構對這兩個特徵以及電子-空穴相互作用的影響。 3由於具有輕巧，柔軟，無毒，低成本和易於加工等優點，半導體共軛聚合物已被廣泛應用於各個領域。這種聚合物的結晶度可以改善光電性能。本主題中的特定科學目標是確定聲子驅動的導熱係數與新引入的聚合物的3D週期性多晶型物之間的關係。" "This project intends to perform a first principle study of physical and chemical properties of periodic systems. Specific targets may be the followings: 1. First-principle simulation study of vibrational spectra of periodic systems 2. Time-dependent functional theory methods for electronic excitations of periodic systems 3. Density functional perturbation theory methods for thermal conductivity of crystalline organic semiconductors. 1. Raman and Terahertz vibrational spectroscopies of molecule-based periodic materials have attracted attention from both experimental spectroscopy groups and the first-principle simulation groups. Vibrational spectroscopy of periodic materials such as polymers, organic-inorganic hybrid perovskites (OIHPs) and metal-organic frameworks (MOFs) provides atomic-scale of information on stacking configurations (polymers, OIHPs), the orientational information of the molecules in (OHIPs, MOFs). Such atomic-scale information is important for understanding the relationship between “molecular parameters” and physical and chemical functionalities of the molecule-based materials. One of the major scientific targets in this topic is to establish the relationship between the spectroscopic feature and the geometrical structures of the above mentioned materials. 2. Theoretical prediction of electronic excitations of periodic systems has still been quite challenging because most of the exact theoretical methods based on many-body Green’s functions (such as GW/BSE (Bethe-Salpeter equation)) approach requires quite demanding computational resources even for simple systems such as graphene. The specific target will be time-dependent density functional theory (TD-DFT) study of (i) how the substitution of the side groups of the polymer affects the optical responses, and (ii) how the coupling of two types of polymers influence the electronic excitations. The effects of stacking configuration on these two features and the electron-hole interactions will be elucidated. 3 The semiconducting conjugated polymers have been used in a broad range of fields owing to advantages such as lightweight, flexible, non-toxic, low-costs, and easy processability. Crystallinity of such polymer may improve optoelectronic properties. The specific scientific goal in the present topic is to determine the relationship between phonon-driven thermal conductivity and 3D periodic polymorph of newly introduced polymers."DFT模擬週期性邊界系統聲子DFT simulationperiodic boundary systemphonon