本研究利用密度泛函理論的 B3LYP 和 B3PW91 泛函數，配合不同基底函數 6-311++G(d,p)、6-311++G(2d,p)及aug-cc-pVTZ計算出HFCS分子、HFCS+(X)離子基態、
與HFCS+(A)離子第一激發態的平衡結構，得到其鍵長與鍵角，也計算了兩者的諧和振動 頻率，雖然分子與離子計算結果無實驗值做對照，但發現六種基組數值已十分貼近，也 與Baker等人[43]的理論計算結果相近，顯示 B3LYP 和 B3PW91 泛函數對於本研究的 計算具有可行性。
在絕熱游離能的計算上，本研究利用CCSD(T)為計算方法，採用B3LYP/aug-cc-pVTZ 基組計算下的平衡結構，求出其能量ECBS，並進行零點能(zero-point energy, ZPE)修正，
求得絕熱游離能與實驗值極為相近，離子基態及第一激發態的計算值為10.16和11.46 eV，
與實驗值的差距分別為0.01和0.03 eV。
最後我們利用量子化學計算所得到的平衡結構和振動模式，再用張嘉麟教授於2013 年開發的FCI計算公式計算出法蘭克-康登因子，並模擬HFCS電離成HFCS+(X)離子基態、
HFCS+(A)離子第一激發態之光電子光譜，再與實驗光電子光譜相比對，結果發現兩者的 光譜型態與實驗光譜極為相似，且在訊號強度分布和相對能量都有極高度類似。
在光譜模擬過程中，我們可從計算出的法蘭克-康登因子明確的辨認 HFCS 分子每 一個躍遷訊號是來自於哪一個振動模式的躍遷、或哪些振動模式組合成的躍遷，並明 確標定之。這相對於實驗光譜來說，要清楚分辨每一個躍遷訊號是十分困難的，但透 過模擬光譜中計算所得的激發能與光譜強度分佈，便能明確的進行實驗光譜的分析與 標定。
總結而言，本研究是第一次對於解析HFCS的光電子光譜提供理論計算的佐證依據，
模擬光譜與實驗光譜吻合，絕熱激發能的計算也與實驗值相當接近，故我們支持Baker 等人觀察到的分子，應是HFCS無誤。本研究顯示，結合理論與實驗的光電子光譜，可 做為鑑定分子的工具之一，未來可進行更多的相關研究，以探究其可行性。
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