Molecular‐Cluster‐Assembly Method for Analysis of High‐Dimensional Structures of p‐Cresol Chains in Phenolic Polymers

Abstract

A new method for analyzing oriented structures of polymers and their formation processes, called ''molecular-cluster-assembly'' (MoCA), is proposed. With this method, a polymer structure is assembled by molecular clusters at local minimum-energy states and comprised of alternating structures along variable atomic coordinates. The reduced conformational space is searched comprehensively by using a Monte Carlo method. The total energy of the polymer structure is calculated from quantum mechanics/ molecular mechanics (QM/MM) energy. It has the same accuracy as full QM energy given by the Mller-Plesset (MP2) method and the fast calculation time is the same as that of the MM method. It is shown that long p-cresol chains form self-organized spiral structures and composite structures with both spirals and open-rings. As phenol groups are oriented towards the inside of the long chains, more oxygen atoms located around a hydrogen atom provide a strong negative potential. It is concluded that these two kinds of oriented structures change the dissociation energy of the hydrogen atoms in the phenol groups. 0.0 0.2 0.4 0.6 0.8

Design of Aggregate Structures and Molecular Capture by Using Molecular‐Cluster‐Assembly Method

“…A schematic diagram of MoCA method is shown in Figure . The calculation procedure consists of three steps and each step is explained in the following:…”

“…Molecular clusters are used as building blocks to build up the oriented molecular structures in a bottom‐up manner. This method, referred to as “molecular‐cluster‐assembly” (MoCA for short), enables us to reduce the problems described above . In the following sections, the MoCA method is briefly explained.…”