Chaban Vitaly V, Andreeva Nadezhda A
Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, 12231-280, São José dos Campos, São Paulo, SP, Brazil.
PRAMO, Saint Petersburg, 197341, Russian Federation.
J Mol Model. 2016 Jan;22(1):26. doi: 10.1007/s00894-015-2896-6. Epub 2016 Jan 7.
Ionic liquids (ILs) constitute a fast growing class of compounds finding multiple applications in science and technology. Morpholinium-based ILs (MBILs) and their mixtures with polar molecular co-solvents are interesting as sustainable electrolyte systems for electrochemistry. We investigate local structures of protic and apropic morpholinium cations in acetonitrile (ACN) using semi-empirical molecular dynamics (MD) simulations. An impact of an anion (acetate) on the cation solvation regularities is discussed. Unlike oxygen, nitrogen of the morpholine ring is a strong electrophilic binding center. This site is responsible for the interactions of the cation with the solvent and with the anion. In protic MBILs, the role of nitrogen is delegated to the proton, which is linked to nitrogen. The acetate anion weakens solvation of the cation due to occupation of space near nitrogen or proton. The analysis reveals a favorable solvation of MBILs in ACN, which is a prerequisite for a new high-performance electrolyte system. The reported structural data were validated through point-to-point comparison with the MP2 post-Hartree-Fock theory and density functional theory.
离子液体（ILs）是一类快速发展的化合物，在科学技术领域有多种应用。基于吗啉鎓的离子液体（MBILs）及其与极性分子共溶剂的混合物作为电化学的可持续电解质体系很受关注。我们使用半经验分子动力学（MD）模拟研究了乙腈（ACN）中质子化和非质子化吗啉鎓阳离子的局部结构。讨论了阴离子（乙酸根）对阳离子溶剂化规律的影响。与氧不同，吗啉环的氮是一个强亲电结合中心。该位点负责阳离子与溶剂以及与阴离子的相互作用。在质子化MBILs中，氮的作用被赋予与氮相连的质子。乙酸根阴离子由于占据氮或质子附近的空间而削弱了阳离子的溶剂化作用。分析表明MBILs在ACN中具有良好的溶剂化作用，这是新型高性能电解质体系的一个先决条件。通过与MP2后哈特里 - 福克理论和密度泛函理论进行点对点比较，验证了所报道的结构数据。
