Molecular dynamics was used to study the aggregation in water of three versions of polyhedral oligomeric silsesquioxane porphyrin (POSSP) molecules. The POSSP molecules have different functional groups; POSSP-IB has one hepta-isobutyl POSS unit, POSSP-Ph has one hepta-phenyl POSS molecule, and POSSP-TIB has four hepta-isobutyl POSS units. Three control porphyrins (TPP, ATPP, TATPP) were also simulated in this study. The effects of the different substituents on the POSSP aggregation process and final morphology were investigated. It is observed that the isobutyl substituents in the POSS units drives the aggregation mainly through the hydrophobic effect. In the case of the phenyl POSS unit, the self-assembly process is also carried through the hydrophobic effect, but π-π and H-bonding interactions play a role too. The final morphology of the aggregates show that the porphyrins associated with POSSP-IB and POSSP-TIB are far apart from each other contrary to POSSP-Ph, which may have a major implication on the optical properties of these aggregates. This study provides valuable insights on the aggregation in water of POSSP molecules, which are a tunable platform to design novel functional materials.

分子动力学用于研究三种形式的多面体低聚倍半硅氧烷卟啉 (POSSP) 分子在水中的聚集。POSSP 分子具有不同的官能团；POSSP-IB有一个七异丁基POSS单元，POSSP-Ph有一个七苯基POSS分子，POSSP-TIB有四个七异丁基POSS单元。本研究还模拟了三种对照卟啉（TPP、ATPP、TATPP）。研究了不同取代基对 POSSP 聚集过程和最终形态的影响。据观察，POSS 单元中的异丁基取代基主要通过疏水作用驱动聚集。在苯基 POSS 单元的情况下，自组装过程也通过疏水作用进行，但 π-π 和 H 键相互作用也起作用。聚集体的最终形态表明与 POSSP-IB 和 POSSP-TIB 相关的卟啉与 POSSP-Ph 相反，彼此相距很远，这可能对这些聚集体的光学性质有重大影响。这项研究为 POSSP 分子在水中的聚集提供了宝贵的见解，POSSP 分子是设计新型功能材料的可调平台。