Dodecagonal quasicrystals of oil-swollen ionic surfactant micelles
Dodecagonal quasicrystals of oil-swollen ionic surfactant micelles
复制标题
DOI：
10.1073/pnas.2101598118
复制
发表时间：
2021-08-03
影响因子：
11.1
通讯作者：
Mahanthappa, Mahesh K.
中科院分区：
文献类型：
--
作者：
Jayaraman, Ashish;Baez-Cotto, Carlos M.;Mahanthappa, Mahesh K.
非共价相互作用的微妙平衡指导分子两亲物的分级自组装成球形胶束，这些胶束包装成三维周期性阵列，其模仿金属间晶体。在此，我们报告的发现，添加水的混合物的离子表面活性剂和正癸烷诱导非周期性有序的油溶胀的球形胶束到以前未被识别的，水性溶致十二方准晶（DDQC），表现出本地12倍旋转对称性和没有远程平移顺序。这些DDQC的出现在动态逮捕胶束玻璃和定期弗兰克-卡斯珀（FK）σ相近似的关系敏感地依赖于组装过程中的分子组分的混合顺序和样品的热历史。添加正癸烷的表面活性剂和水的混合物，而不是导致周期FK A15和西格玛近似没有证据的非周期性秩序，而延长的环境温度退火的DDQC也揭示了它的转变成西格玛相。因此，这些溶致DDQC是长寿命的亚稳态形态，其从胶束尺寸的随机分布成核和生长，所述胶束尺寸的随机分布通过在水合时不同量的油突然分离成表面活性剂胶束而形成。这些发现表明，分子构建块的复杂性不是形成非周期性超分子秩序的先决条件，同时也建立了跨金属合金和自组装胶束材料的准晶状态的一般性质。
A delicate balance of noncovalent interactions directs the hierarchical self-assembly of molecular amphiphiles into spherical micelles that pack into three-dimensional periodic arrays, which mimic intermetallic crystals. Herein, we report the discovery that adding water to a mixture of an ionic surfactant and n-decane induces aperiodic ordering of oil-swollen spherical micelles into previously unrecognized, aqueous lyotropic dodecagonal quasicrystals (DDQCs), which exhibit local 12-fold rotational symmetry and no long-range translational order. The emergence of these DDQCs at the nexus of dynamically arrested micellar glasses and a periodic Frank-Kasper (FK) sigma phase approximant sensitively depends on the mixing order of molecular constituents in the assembly process and on sample thermal history. Addition of n-decane to mixtures of surfactant and water instead leads only to periodic FK A15 and sigma approximants with no evidence for aperiodic order, while extended ambient temperature annealing of the DDQC also reveals its transformation into a sigma phase. Thus, these lyotropic DDQCs are long-lived metastable morphologies, which nucleate and grow from a stochastic distribution of micelle sizes formed by abrupt segregation of varied amounts of oil into surfactant micelles on hydration. These findings indicate that molecular building block complexity is not a prerequisite for the formation of aperiodic supramolecular order, while also establishing the generic nature of quasicrystalline states across metal alloys and self-assembled micellar materials.