一个简单的规则,用于根据红外频率模式对多化二子-p-二氧化物同源进行分类
1Department of Chemistry, PaiChai University, 493-6 Doma-dong, Seoku, Taejun 302-735, Korea.
Journal of the American Chemical Society
|July 27, 2001
概括
这项研究简化了多二二二氧化物 (PCDD) 的IR光谱分析,通过根据替代分组成10种模式. 一个独特的1392厘米的峰值可以识别有毒的PCDD原体.
科学领域:
- 计算化学的计算化学
- 频谱学是一种光谱学.
- 环境科学 环境科学
背景情况:
- 多二二二氧化物 (PCDD) 是具有复杂红外 (IR) 光谱的持久性有机污染物.
- 准确识别和量化PCDD原体对于环境监测和风险评估至关重要.
研究的目的:
- 开发一种简化方法来分析PCDD原体的IR光谱.
- 为了确定替代模式和特征性的内射频率之间的相关性.
- 为了识别有毒PCDD原体的独特光谱标记物.
主要方法:
- 使用B3LYP方法的密度函数理论 (DFT) 计算被用于计算76种二氧化物同源的IR光谱.
- 分析计算的光谱,以确定与替代相关的模式.
- 基于共同的结构动机的光谱频率的分类.
主要成果:
- 建立了PCDD的IR光谱分析的简单规则,根据替代模式将同源物分为10组.
- 一个环中的化对另一环的振动频率影响最小.
- 对于所有带有侧面化 (位置2,3,7,8) 的有毒PCDD原体,确定了一个独特的IR峰值,约为1392cm(-1),对应于b(1u) 模式.
结论:
- 该研究简化了复杂的PCDDIR光谱分析,以确定两个主要峰值,每个峰值代表一个化环.
- 振动频率的系统趋势归因于替代物的质量效应.
- 具有特征的1392cm(-1) 峰值是识别有毒PCDD原生物的一种可靠指标.
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