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用低频拉曼和特拉赫兹振动光谱仪对有机火药残留物进行表征

Salvatore Zarrella¹, Margaret P Davis¹, Mary N Boyden¹

¹Department of Chemistry, Syracuse University, 3-014 Center for Science and Technology, Syracuse, New York 13244-4100, United States.

|February 16, 2026

概括

低频振动光谱,包括拉曼和太赫兹时域光谱,可以有效地区分类似的有机火药残留物. 低频拉曼光谱对检测乙基和甲基中央石更为敏感.

科学领域:

法医科学法医科学法医科学
分析化学分析化学
材料科学材料科学材料科学

背景情况:

固态有机火药残留物 (OGSRs) 是刑事调查中的关键痕迹证据.
低频振动光谱 (10-300厘米-1) 探测网格振动,提供独特的光谱指纹用于化合物识别.
太赫兹时域光谱 (THz-TDS) 和低频拉曼光谱 (LFRS) 是分析这些振动的先进技术.

研究的目的:

使用LFRS和THz-TDS分析和区分结构相似的OGSR,特别是乙烯中央和甲基中央.
使用固态密度函数理论 (DFT) 模拟来解释光谱数据.
评估LFRS和THz-TDS在OGSR检测和量化方面的敏感性和适用性.

主要方法:

获取纯乙基中央和甲基中央的LFRS和THz-TDS光谱.
使用固态密度函数理论 (DFT) 来理解光谱起源的计算分析.
测量二元混合物以评估分化能力.

主要成果:

对于乙基中央石和甲基中央石,尽管它们的结构相似,但观察到不同的LFRS和THz-TDS光谱.
DFT模拟表明,环扭转运动,而不是分子间转换,主导着最强的光谱特征.
低频拉曼光谱显示出更高的灵敏度,为乙基中央石确定了98.8厘米-1的特征峰值,为甲基中央石确定了111.7厘米-1.

结论:

低频振动光谱,特别是LFRS,是可靠检测和量化特定OGSRs (如基化二尿素) 的强大工具.
已识别的光谱标记为未来的法医分析提供了实际的实用性.
这项研究强调了低频振动光谱在法医科学应用中的显著但尚未探索的潜力.

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