Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2013 Mar;104:358-67. doi: 10.1016/j.saa.2012.11.082. Epub 2012 Dec 5.
Density functional theory (DFT) calculations are being performed to investigate the geometric, vibrational, and electronic properties of the chlorogenic acid isomer 3-CQA (1R,3R,4S,5R)-3-{[(2E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl]oxy}-1,4,5-trihydroxycyclohexanecarboxylic acid), a major phenolic compound in coffee. DFT calculations with the 6-311G(d,p) basis set produce very good results. The electrostatic potential mapped onto an isodensity surface has been obtained. A natural bond orbital analysis (NBO) has been performed in order to study intramolecular bonding, interactions among bonds, and delocalization of unpaired electrons. HOMO-LUMO studies give insights into the interaction of the molecule with other species. The calculated HOMO and LUMO energies indicate that a charge transfer occurs within the molecule.
密度泛函理论（DFT）计算正在进行中，以研究咖啡中主要酚类化合物 3-咖啡酰奎宁酸（1R,3R,4S,5R）-3-[[（2E）-3-（3,4-二羟基苯基）丙烯酰基]氧基]-1,4,5-三羟基环己烷羧酸（3-CQA）的几何、振动和电子性质。使用 6-311G(d,p)基组进行的 DFT 计算产生了非常好的结果。已经获得了映射到等密度表面的静电势。进行了自然键轨道分析（NBO），以研究分子内键合、键之间的相互作用以及未配对电子的离域。HOMO-LUMO 研究提供了分子与其他物质相互作用的深入了解。计算的 HOMO 和 LUMO 能量表明分子内发生了电荷转移。
