二氰胺根分子内费米振动耦合能量转移的超快二维红外光谱

Fermi-Coupling and Intramolecular Vibrational Energy Transfer in Dicyanamide Examined by Ultrafast Infrared Spectroscopy

二氰胺根离子(N(CN)-2,DCA)的C≡N对称及反对称伸缩振动(νas,C≡N和νss,C≡N)和N—C伸缩振动的和频峰(νas,N—C+νss,N—C)之间由于费米共振作用存在振动耦合。本文研究了二氰胺钠在DMSO溶液中的超快二维红外(2DIR)光谱和超快红外泵浦探测(IR PP)光谱。结合该体系的傅里叶变换红外(FTIR)光谱实验结果,对二氰胺根离子体系中的分子内振动能量转移过程进行了分析。

Nitrile antisymmetric stretch(νas,C≡N),symmetric stretch(νss,C≡N)and the N—C combination(νas,N—C+νss,N—C)modes of dicyanamide(N(CN)-2,DCA)were found to be coupled due to Fermi-resonance.Here,two-dimensional infrared(2D IR)and ultrafast infrared pump-probe(IR PP)spectroscopies of dicyanamide in DMSO were studied.By combining Fourier transform infrared(FTIR)experimental result,the intramolecular vibrational energy transfer processes of dicyanamide were presented and discussed.