Experimental and theoretical structure and vibrational analysis of ethyl trifluoroacetate, CF 3 CO 2 CH 2 CH 3
Experimental and theoretical structure and vibrational analysis of ethyl trifluoroacetate, CF 3 CO 2 CH 2 CH 3
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三氟乙酸乙酯CF 3 CO 2 CH 2 CH 3 的实验和理论结构及振动分析
DOI：
10.1002/jrs.2550
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发表时间：
2009
影响因子：
2.5
通讯作者：
Defonsi Lestard M
中科院分区：
文献类型：
--
作者：
Defonsi Lestard M
采用电子衍射、红外光谱和拉曼光谱等方法测定了三氟乙酸乙酯CF3CO2CH2CH3的分子结构和构象性质。实验研究在不同理论水平上辅以从头算（MP2）和DFT量子化学计算。实验和理论方法得到了cs（反反）和c1（反间扭）对称的两种结构，前者比后者稍微稳定一些。电子衍射数据最适合于56%的反扭扭构象和44%的反反构象的混合物。用总能量表和天然键轨道表研究了其构象偏好。此外，报告了cf3co2ch2ch3的气体、液体和固体的红外光谱，以及液体的拉曼光谱。对比了c_2和c1构象的实验平均红外光谱，为预测的构象提供了依据。计算了两种构象的谐波振动波数和标度力场。版权所有©2009 John Wiley & Sons， Ltd
The molecular structure and conformational properties of ethyl trifluoroacetate, CF3CO2CH2CH3, were determined in the gas phase by electron diffraction, and vibrational spectroscopy (IR and Raman). The experimental investigations were supplemented byab initio(MP2) and DFT quantum chemical calculations at different levels of theory. Experimental and theoretical methods result in two structures withCs(anti–anti) andC1(anti–gauche) symmetries, the former being slightly more stable than the latter. The electron‐diffraction data are best fitted with a mixture of 56%anti–gaucheand 44%anti–anticonformers. The conformational preference was also studied using the total energy scheme, and the natural bond orbital scheme. Also, the infrared spectra of CF3CO2CH2CH3are reported for the gas, liquid and solid states, as is the Raman spectrum of the liquid. The comparison of experimental averaged IR spectra ofCsandC1conformers provides evidence for the predicted conformations in the IR spectra. Harmonic vibrational wavenumbers and scaled force fields have been calculated for both conformers. Copyright © 2009 John Wiley & Sons, Ltd.