Lo Celso F, Yoshida Y, Castiglione F, Ferro M, Mele A, Jafta C J, Triolo A, Russina O
Dipartimento di Fisica e Chimica, viale delle Scienze, ed. 17, 90128 Palermo, Italy.
Phys Chem Chem Phys. 2017 May 24;19(20):13101-13110. doi: 10.1039/c7cp01971h.
Fluorinated room temperature ionic liquids (FRTILs) represent a class of solvent media that are attracting great attention due to their IL-specific properties as well as features stemming from their fluorous nature. Medium-to-long fluorous tails constitute a well-defined apolar moiety in the otherwise polar environment. Similarly to the case of alkyl tails, such chains are expected to result in the formation of self-assembled fluorous domains. So far, however, no direct experimental observation has been made of the existence of such structural heterogeneities on the nm scale. We report here the first experimental evidence of the existence of mesoscopic spatial segregation of fluorinated domains, on the basis of highly complementary X-ray and neutron scattering data sets (highlighting the importance of the latter probe) and NMR spectroscopy. Data are interpreted using atomistic molecular dynamics simulations, emphasizing the existence of a self-assembly mechanism that delivers segregated fluorous domains, where preferential solubilisation of fluorinated compounds can occur, thus paving the way for several smart applications.
氟化室温离子液体（FRTILs）是一类溶剂介质，由于其离子液体特有的性质以及源自其氟代性质的特征而备受关注。中长氟代链在原本极性的环境中构成了一个明确的非极性部分。与烷基链的情况类似，这样的链预计会导致自组装氟代域的形成。然而，到目前为止，尚未对纳米尺度上这种结构异质性的存在进行直接的实验观察。我们在此报告基于高度互补的X射线和中子散射数据集（突出了后者探针的重要性）以及核磁共振光谱，首次获得了氟化域介观空间分离存在的实验证据。使用原子分子动力学模拟对数据进行解释，强调存在一种自组装机制，该机制产生分离的氟代域，在其中可以发生氟化化合物的优先溶解，从而为多种智能应用铺平了道路。
