DMREF: Computer-aided Design of Hierarchical Molecular Materials

Indiana University, Bloomington IN

Investigators

Abstract

DMREF: Computer-aided Design of Hierarchical Molecular Materials Non-technical Description: Organic materials that spontaneously order into specific architectures could significantly advance our ability to harvest solar energy. However, developing these materials in traditional ways is a tedious process. This project will integrate computer-aided design (CAD), synthesis, and characterization to make a transformative approach in ordered organic materials discovery. An Indiana University team will study packing interactions and develop CAD algorithms for organic architectures. The architectures will form by spontaneous interactions of molecular building blocks programmed with specific features that connect them with neighbors. Resulting architectures will be characterized with state-of-the-art microscopy at single molecule resolution. Those data will be used to improve the design algorithm to reliably predict two-dimensional packing and film growth on surfaces. This algorithm will be implemented as computer software to supersede experiment and thus allow vast speed-ups in the discovery of new organic materials for harvesting solar energy. This work will have a broad impact on many applications of organic materials through free distribution of the design software and through national scientific symposia. The project will also sponsor recruitment of under-represented groups to scientific research careers and outreach to engage high school students in nanoscience education, thus impacting the next generation of scientists. Technical Description: It is understood that blending two types of organic polymers with 10-20 nm feature sizes is advantageous in photovoltaic devices, but, at present, we do not know how to program organic molecules to form organized bulk heterojunctions with these feature sizes. This project will apply an integrated theory-experiment approach to the programming of molecular self-assembly. Multiscale simulations will be implemented as the core of a materials CAD platform. Innovations in multiscale molecular dynamics will be used to accelerate computation. Batch execution of simulations will be automated by database-backed software. CAD results will be used to design molecules that will be synthesized and allowed to self-assemble at the solution-solid interface. 2D and 3D architectures will be characterized using molecular-resolution scanning tunneling microscopy. Continuous feedback between CAD and the resulting architectures will accelerate the discovery of highly ordered multilayer films. The self-organization of two-component mixtures into alternating domains will be investigated. CAD software will be made available for others to use in the creation of novel organic materials.