Surface enhanced Raman scattering (SERS) has great potential as an alternative tool for arsenic speciation in biological matrices. SERS measurements have advantages over other techniques due to its ability to maintain the integrity of arsenic species and its minimal requirements for sample preparation. Up to now, very few Raman spectra of arsenic compounds have been reported. This is particularly true for thiolated arsenicals, which have recently been found to be widely present in humans. The lack of data for Raman spectra in arsenic speciation hampers the development of new tools using SERS. Herein, we report the results of a study combining the analysis of experimental Raman spectra with that obtained from density functional calculations for some important arsenic metabolites. The results were obtained with a hybrid functional B3LYP approach using different basis sets to calculate Raman spectra of the selected arsenicals. By comparing experimental and calculated spectra of dimethylarsinic acid (DMA^V), the basis set 6-311++G** was found to provide computational efficiency and precision in vibrational frequency prediction. The Raman frequencies for the rest of organoarsenicals were studied using this basis set, including monomethylarsonous acid (MMA^III), dimethylarsinous acid (DMA^III), dimethylmonothioarinic acid (DMMTA^V), dimethyldithioarsinic acid (DMDTA^V), S-(Dimethylarsenic) cysteine (DMA^III(Cys)) and dimethylarsinous glutathione (DMA^IIIGS). The results were compared with fingerprint Raman frequencies from As─O, As─C, and As─S obtained under different chemical environments. These fingerprint vibrational frequencies should prove useful in future measurements of different species of arsenic using SERS.

表面增强拉曼散射（SERS）作为生物基质中砷形态形成的替代工具具有巨大潜力。SERS测量具有比其他技术更高的优势，这是因为它具有保持砷物种完整性的能力以及对样品制备的最低要求。迄今为止，几乎没有关于砷化合物的拉曼光谱的报道。对于最近被发现广泛存在于人类中的硫醇化砷尤其如此。砷形态中拉曼光谱数据的缺乏阻碍了使用SERS的新工具的开发。在此，我们报告了一项研究结果，该研究结果结合了实验拉曼光谱的分析与从密度函数计算中获得的一些重要砷代谢物的分析结果。通过使用不同基集的混合功能性B3LYP方法获得的结果来计算所选砷的拉曼光谱。通过比较二甲基砷酸（DMA）的实验和计算光谱^V），发现基集6-311 ++ G **可提供振动频率预测的计算效率和精度。使用此基集研究了其余有机砷的拉曼频率，包括一甲基ar酸（MMA ^III），二甲基ar酸（DMA ^III），二甲基一硫代砷酸（DMMTA ^V），二甲基二硫代砷酸（DMDTA ^V），S-（二甲基砷）半胱氨酸（DMA ^III（Cys））和二甲基ar谷胱甘肽（DMA ^IIIGS）。将结果与在不同化学环境下获得的As-O，As-C和As-S的指纹拉曼频率进行了比较。这些指纹振动频率应被证明在将来使用SERS测量不同种类的砷时很有用。