The structure of aqueous solutions of hexafluoro-iso-propanol studied by neutron diffraction with hydrogen/deuterium isotope substitution and empirical potential structure refinement modeling
The structure of aqueous solutions of hexafluoro-iso-propanol studied by neutron diffraction with hydrogen/deuterium isotope substitution and empirical potential structure refinement modeling
复制标题
通过氢/氘同位素取代的中子衍射和经验势结构细化模型研究六氟异丙醇水溶液的结构
DOI：
10.1039/d1cp00950h
复制
发表时间：
2021
影响因子：
3.3
通讯作者：
J. L. Finney
中科院分区：
文献类型：
--
作者：
K. Yoshida;T. Yamaguchi;D. T. Bowron;J. L. Finney
在室温下对七种H/D取代的六氟异丙醇（HFIP; 1，1，1，3，3，3-六氟-2-丙醇）-水混合物在0.1，0.2和0.4HFIP摩尔分数（xHFIP）下进行H/D同位素取代的中子衍射测量。除了H（CH）-H（CH）对获得的8个部分结构因子进行了经验势结构精化（EPSR）方法，以获得所有的网站网站对相关函数。据发现，随着HFIP浓度的增加，冰状网络的水消失之间的xHFIP = 0.1和0.2，随后由一个链状水结构的形成嵌入在一个内在的结构中的HFIP演变在xHFIP = 0.4。HFIP的羟基与周围的水分子在所有HFIP的摩尔分数研究形成氢键。没有证据表明HFIP的CF 3基团周围有明确的水结构，但水分子切向地围绕HFIP的CF 3基团。
Neutron diffraction measurements of H/D isotopic substitution are made at room temperature for seven H/D substituted hexafluoro-iso-propanol (HFIP; 1,1,1,3,3,3-hexafluoro-2-propanol)–water mixtures at 0.1, 0.2, and 0.4 HFIP mole fraction (xHFIP). The eight partial structure factors except for the H(CH)–H(CH) pair obtained are subjected to an empirical potential structure refinement (EPSR) method to derive all site–site pair correlation functions. It is found that with increasing HFIP concentration the ice-like network of water disappears between xHFIP = 0.1 and 0.2, followed by the formation of a chain-like water structure embedded in an intrinsic structure of HFIP evolved at xHFIP = 0.4. The hydroxyl group of HFIP forms hydrogen bonds with the surrounding water molecules at all HFIP mole fractions investigated. There is no evidence that the water structure is well defined around the CF3 groups of HFIP, but water molecules surround tangentially the CF3 groups of HFIP.