Infrared spectra of the β and γ phases of oleic acid under high pressure
Infrared spectra of the β and γ phases of oleic acid under high pressure
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高压下油酸β相和γ相的红外光谱
DOI：
10.1016/j.saa.2021.120290
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Fujihisa Hiroshi
中科院分区：
文献类型：
--
作者：
Yamawaki Hiroshi;Fujihisa Hiroshi
在室温（~25 °C）下，在高达5和10 GPa的压力下，分别获得了油酸的β和γ相的红外光谱。密度泛函理论（DFT）计算进行了检查的红外光谱和晶格的β和γ相的压力下发生的变化。基于DFT计算的红外光谱，对观察到的具有随压力低波数偏移的峰进行模式分配。β相和γ相的C双键O伸缩振动和O单键H伸缩振动峰均随压力向低波数方向移动，这是因为压力使氢键增强，C双键O和O单键H键减弱。两相之间的位移量的差异与晶格中的各向异性压缩有关。
Infrared spectra for theβandγphases of oleic acid were obtained at room temperature (~25 °C) under pressures of up to 5 and 10 GPa, respectively. Density functional theory (DFT) calculations were performed to examine the changes in the infrared spectra and crystal lattices of theβandγphases that occur under pressure. Mode assignments for peaks that were observed to have a low-wavenumber shift with pressure were made based on the DFT-calculated infrared spectra. The Cdouble bondO stretching and Osingle bondH stretching vibration peaks shifted to a lower wavenumber with pressure in both theβandγphases because the hydrogen bonds became stronger with pressure and the Cdouble bondO and Osingle bondH bonds weakened. The difference in the shift amount between the two phases was related to anisotropic compression in the crystal lattice.