眾所皆知，石墨烯和矽烯等第四族元素所形成的二維結構材料，由於獨特的結構、電子特性及化學特性等，已經是現階段非常熱門的討論對象。本碩士論文主要以VASP作為計算工具，來進行第一原理的詳細數值計算，以模擬晶體的電子密度分布，並探討其中的各種特性。
主要研究物質是極對稱下的矽烯吸附鋁原子，討論不同濃度和排列方式來吸附所造成的幾何結構、電子特性、電荷分布和態密度（density of state, DOS）變化，並藉由調控濃度來了解其吸附情形和鍵結變化趨勢，再探討複雜的混成軌域所造成的能帶劇烈破壞。另一方面，利用電荷密度分布及轉移情況來釐清鍵能的運作模式，透過軌域投影態密度（orbital-projected density of state, PDOS）的貢獻表示，更透徹的分析能帶結構，且由態密度和空間中的電荷分布，再次驗證矽鋁鍵結所表現出的多元特性。

Graphene, silicene, and group IV graphene-related systems have already been very popular subjects for quite some time. Especially, it has unique structural, electronic properties and chemical properties. In this thesis, we use the first principle calculations to study the properties and simulate the electron density distribution of crystal by VASP.
The study focuses on aluminum-adsorbed silicene, considering the case of extreme symmetric. Geometric structures, electronic Structures, charge distributions, and density of states (DOS) strongly depend on the different configurations and the various concentrations of aluminum adatoms. We research the adsorption of atoms and trend of bondings which can be remarkably modulated by Al-concentrations, investigating serious destruction of electronic structures with complex orbital hybridizations. On the other hand, the use of electron density distribution and charge transfer can clarify the operation of bond energy. The orbital-projected density of state (PDOS) can analyze the band structures in detail. The DOS and spatial charge distributions clearly indicate that the special bonds in Si-Si and Al-Si are responsible for the diversified properties.

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