Application of derivative method in infrared spectroscopy experimental teaching of paraffin oil molecular structure
Wang Xin1, Yao Jianhui2, Ji Yifan1, Li Yuhan1, Duan Bingjie1, Li Shuangfan1,#br#
Gao Meiting1, Yu Hongwei1,3
1. Shijiazhuang University, School of Chemical Engineering, Shijiazhuang 050035, China; 2. China Petroleum and Chemical Corporation, Shijiazhuang Refining and Chemical Branch, Shijiazhuang 050035, China; 3. Anesthetic Technology Innovation Center of Hebei Province, Shijiazhuang 050035, China
The molecular structure of paraffin oil was studied using mid infrared (MIR) spectroscopy (including one-dimensional MIR spectroscopy, first-order derivative MIR spectroscopy, second-order derivative MIR spectroscopy, third-order derivative MIR spectroscopy, and fourth-order derivative MIR spectroscopy). The experiment found that the infrared absorption mode of paraffin oil molecular structure mainly includes: CH3 group asymmetric stretching vibration mode (ν■), CH3 group symmetric stretching vibration mode (ν■), CH2 group asymmetric stretching vibration mode (ν■), CH2 group symmetric stretching vibration mode (ν■), CH2 group bending vibration mode (δ■), CH3 groups asymmetric bending vibration mode (δ■), CH3 groups symmetric bending vibration mode (δ■) and CH2 group in-plane rocking vibration mode (ρ■). Research has found that the molecular structure of paraffin oil spectral resolution of second-order derivative MIR spectroscopy is superior to corresponding one-dimensional MIR molecular spectroscopy, first-order derivative MIR spectroscopy, third-order derivative MIR spectroscopy, and fourth-order derivative MIR spectroscopy. Selecting appropriate smoothing points (including 5 smoothing points, 9 smoothing points, 13 smoothing points, 19 smoothing points, 25 smoothing points, 37 smoothing points, 49 smoothing points, and 149 smoothing points) can effectively improve the resolution ability of second-order derivative MIR spectra, providing theoretical support and practical application reference for expanding the application field of MIR spectroscopy in clinical medicine.
王 欣1，姚建辉2，吉一帆1，李宇涵1，段冰洁1，李泷帆1，高梅婷1，于宏伟1,3. 导数法在石蜡油分子结构中红外光谱实验教学中的应用[J]. 煤炭与化工, 2025, 48(5): 143-149,160..
Wang Xin1, Yao Jianhui2, Ji Yifan1, Li Yuhan1, Duan Bingjie1, Li Shuangfan1,. Application of derivative method in infrared spectroscopy experimental teaching of paraffin oil molecular structure. CCI, 2025, 48(5): 143-149,160..
