近年來因為石墨烯的獨特導電性，石墨烯的特性讓二維材料越來越吸引人，然而石墨烯為半金屬且自旋軌道耦合效應很小幾乎可以忽略，所以我們研究室開始研究同為第四族的矽烯和鍺烯，在理論計算得出矽烯和鍺烯可以由外加電場控制能隙，矽烯和鍺烯實驗製備和各式各樣的參雜的理論計算就越來越熱門且重要，二維材料的光學導電磁性等性質就足以引向下個世代的材料。本碩士論文主要以VASP作為計算工具，進行第一原理的詳細數值計算，模擬晶體的電子密度分佈，並研究其中的各種特性。
主要研究為鍺烯吸附過渡金屬鐵、鈷、鎳，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佈態密度自旋分佈。鍺原子之間的化學鍵結強度小於鐵鈷鎳與鍺原子之間的鍵結強度，造成鍺烯參雜鐵鈷鎳時會有最高濃度的問題，鍺烯在受到過渡金屬d軌域自旋軌道耦合影響下會出現半導體及金屬及鐵磁性的自旋分佈。

We mainly study the geometric structure, band structure, charge density, charge density difference, spin distribution, and density of states after the adsorption of iron, cobalt, and nickel germanene, and define chemical images from various physical quantities, from germanene and adsorption The bonding of atoms determines or judges how the chemical orbital mix determines the geometric structure.
We use the Vienna Ab-initio Simulation Package (VASP) as our first-principles calculation tool, consider the spin-orbit interaction during our calculations, and precalculate the magnetic properties in our system.
After our calculations, we found that there is a limit to the highest concentration of germanene adsorbing iron, cobalt, and nickel. After calculating at different positions, we found that placing adsorbed atoms in adjacent adsorption positions would destroy the structure of germanene. It can be seen from the spin distribution, magnetic moment, and energy band that the system is found to be ferromagnetic after iron and cobalt are adsorbed, but there is no magnetism in the nickel system.
We found that there is the highest concentration after the adsorption of Fe, Co, and Ni. We have never found anyone mentioning this when reviewing the article on the same system. The adsorption of iron and cobalt at different concentrations shows multiple energy band properties.
Keywords: solid state physics, first principles, germanene, transition metal iron、cobalt 、nickel adsorption, magnetism

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