Application of Two-Trace Two-Dimensional Asynchronous Correlation Spectroscopy in Characterizing Intermolecular Interactions: A Feasibility Study
LI Xiao-pei1*, ZHANG Yong-jie2，XUE Li-zhen1
1. Instrumental Analysis Center, Dalian Polytechnic University, Dalian 116034, China
2. School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
Abstract：Two-trace two-dimensional (2T2D) asynchronous correlation spectroscopy is a new method of generating two-dimensional asynchronous correlation spectroscopy based on a pair of one-dimensional (1D) spectra. Compared with the conventional two-dimensional asynchronous correlation spectroscopy where at least three 1D spectra are needed, 2T2D asynchronous correlation spectroscopy makes the experiment easier, and is a better method for the expensive samples. In the present paper, the feasibility of using 2T2D asynchronous correlation spectroscopy to characterize intermolecular interactions was explored. Firstly, a model system containing two solutes P and Q were set up. P possessed a characteristic peak, and Q had no characteristic peaks. The mathematical analysis demonstrated that the intensity of 2T2D asynchronous correlation spectra was always zero when the initial concentrations of P and Q were set incorrectly. Furthermore, the variations of the absorptivity induced by intermolecular interactions could not be discerned by 2T2D-asynchronous correlation spectra. Therefore, incorrect results may be obtained when 2T2D asynchronous correlation spectroscopy is adopted to characterize intermolecular interactions. In order to develop 2T2D asynchronous correlation spectroscopy into a reliable method for characterizing intermolecular interactions, the setting method of the initial concentrations of P and Q in the 2T2D asynchronous correlation spectroscopy was first studied. The case that the intensity of 2T2D asynchronous correlation spectra was always zero induced by incorrectly setting the initial concentrations of P and Q could be avoided when the initial concentrations of P and Q satisfied the requirement of Eq.(6) in the text. On this basis, the 2T2D-asynchronous correlation spectroscopy with auxiliary cross peaks (ASAP-2T2D-asynchronous correlation spectroscopy) was developed by introducing a virtual substance S with an isolated peak and proper concentration into the research system to solve the problem that 2T2D-asynchronous correlation spectra could not reflect the variations of the absorptivity induced by intermolecular interactions. The results of computer simulation experiments demonstrated that the ASAP-2T2D-asynchronous correlation spectra could correctly reflect the variation of the peak position, bandwidth and absorptivity indicating that the ASAP-2T2D-asynchronous correlation spectroscopy was a reliable method for characterizing intermolecular interactions. Finally, the ASAP-2T2D-asynchronous correlation spectroscopy was adopted to characterize the intermolecular interaction between Li+ and benzo-15-crown-5 (BC). The results demonstrated that the variation of the peak position and absorptivity of the characteristic peak of BC could be reflected by the ASAP-2T2D-asynchronous correlation spectrum. These results further confirmed that the ASAP-2T2D-asynchronous correlation spectroscopy could correctly characterize intermolecular interactions.
Key words：Intermolecular interactions; 2T2D-asynchronous correlation spectroscopy; Auxiliary cross peaks
[1] Jia H Y, Huang Z J, Fei Z F, et al. Journal of Materials Chemistry B, 2017, 5: 8193.
[2] Mitsuhashi R, Suzuki T, Hosoya S, et al. Crystal Growth & Design, 2017, 17: 207.
[3] Kolá( rˇ ) M H, Hobza P. Chemical Reviews, 2016, 116: 5155.
[4] Chen P Y, Zhang L, Zhu S G, et al. Journal of Molecular Structure, 2017, 1131: 250.
[5] Yim D B, Kim J E, Kim H I, et al. Small, 2018, 14: 1800026.
[6] Kang M, Zhang P C, Cui H G, et al. Macromolecules, 2016, 49: 994.
[7] WANG Yan, LÜ Da, GUO Ming, et al(王 燕, 吕 达, 郭 明, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2018, 38（2）: 494.
[8] Alanazi A M, Abdelhameed A S, Bakheit A H, et al. Journal of Molecular Liquids, 2017, 238: 3.
[9] Yang F L, Yang X, Wu R Z, et al. Physical Chemistry Chemical Physics, 2018, 20: 11386.
[10] HAN Guo-cheng, SU Xiao-rui, HOU Jia-ting, et al(韩国成, 苏晓瑞, 侯嘉婷，等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2018, 38(12): 3958.
[11] Wu Y Q, Zhang L P, Jung Y M, et al. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2018, 189: 291.
[12] He A Q, Zeng X Z, Xu Y Z, et al. Journal of Physical Chemistry A, 2017, 121: 7524.
[13] Noda I. Journal of Molecular Structure, 2018, 1160: 471.
[14] Li X P, He A Q, H K, et al. RSC Advances, 2015, 5: 87739.
