摘要
在研究奈米科學的理論時不但許多物理現象可能會違背巨觀世界下的理論，而且在實驗量測上也頗具困難度，分子動力學模擬成為奈米科學重要的研究工具。另一方面，在能源短缺的今日，燃料電池的研究成為一熱門課題，其中又以直接甲醇燃料電池（DMFC）高能量密度之特性而備受矚目，所以當DMFC發展越趨向微小化，其燃料—甲醇水溶液在微觀尺度下的性質研究就更顯重要。
本研究以分子動力學理論為基礎進行程式設計，模擬甲醇分子在常溫液態與超臨界狀態下均質系統中下相關的物質特性，例如系統總能量、逕向結構分佈函數、自我擴散係數、氫鍵配位數等，並與文獻中的理論分析或實驗結果做驗證，提出物理解釋與探討。之後又將甲醇分子與水分子混合成甲醇水溶液，模擬其系統總能量以及氧原子和氫原子間的逕向結構分佈函數，希望對於甲醇水溶液中分子氫鍵的現象提出部份觀查和解釋。
模擬結果發現甲醇液體的擴散速率與隨溫度增加而升高，且確認分子間氫鍵作用距離約為1.86 ；隨模擬溫度的提高，分子間氫鍵數呈現下降趨勢，於超臨界狀態下氫鍵效應幾乎完全消失。此外，甲醇水溶液會因莫耳分率越高而總能量越低，根據氫氧原子間逕向結構分佈函數的分析，認為甲醇與水混合時可能沒有唯一特定的氫鍵距離。

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