Ansar Siyam M, Li Xiaoxia, Zou Shengli, Zhang Dongmao
Department of Chemistry, Mississippi State University , Mississippi State, Mississippi 39762, United States.
Department of Sciences and Mathematics, Mississippi University for Women , Columbus, Mississippi 39701, United States.
J Phys Chem Lett. 2012 Mar 1;3(5):560-5. doi: 10.1021/jz2016439. Epub 2012 Feb 9.
Studying the correlation between the molecular structures of SERS-active analytes and their SERS enhancement factors is important to our fundamental understanding of SERS chemical enhancement. Using a common internal reference method, we quantitatively compared the Raman activities, SERS activities, and SERS enhancement factors for a series of organothiols that differ significantly in their structural characteristics and reported chemical enhancements. We find that while the tested molecules vary tremendously in their normal Raman and SERS activities (by more than 4 orders of magnitude), their SERS enhancement factors are very similar (the largest difference is less than 1 order of magnitude). This result strongly suggests that SERS chemical enhancement factors are not as diverse as initially believed. In addition to shedding critical insight on the SERS phenomena, the common internal reference method developed in this work provides a simple and reliable way for systematic investigation of the correlation between molecular structures and their normal Raman and SERS activities.
研究表面增强拉曼散射（SERS）活性分析物的分子结构与其SERS增强因子之间的相关性，对于我们从根本上理解SERS化学增强至关重要。通过使用一种常见的内参方法，我们定量比较了一系列结构特征和报道的化学增强差异显著的有机硫醇的拉曼活性、SERS活性和SERS增强因子。我们发现，虽然所测试的分子在其正常拉曼和SERS活性方面差异极大（超过4个数量级），但其SERS增强因子却非常相似（最大差异小于1个数量级）。这一结果有力地表明，SERS化学增强因子并不像最初认为的那样多样。除了对SERS现象提供关键见解外，本工作中开发的常见内参方法为系统研究分子结构与其正常拉曼和SERS活性之间的相关性提供了一种简单可靠的方法。
