Journal
JOURNAL OF PHYSICAL CHEMISTRY C
Volume 122, Issue 16, Pages 9141-9151Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jpcc.7b11271
Keywords
-
Funding
- Volkswagen Foundation [A115678]
- Russian Science Foundation [16-13-00111]
- U.S. Department of Energy (DOE) Office of Science [DE-AC52-06NA25396]
- Sandia National Laboratories [DE-AC04-94AL85000]
Ask authors/readers for more resources
We systematically study low-energy crystalline polymorphs of the archetypal conjugated polymer, regioregular poly-3-hexylthiophene (rr-P3HT) using the best available density functional theory methods benchmarked against the ab initio coupled cluster method. A comprehensive conformational search is performed for two-dimensional pi-stacks being the most rigid structural unit of bulk P3HT. We have identified a number of nearly isoenergetic polymorphs below the energy level of room-temperature amorphous structures and well below the energy of optimized best-fit experimental models. Classical molecular dynamics simulations show that these crystals retain their structure at least at 200 K. At room temperature, although the conjugated backbone of the pi-stack remains ordered, aliphatic side chains are melted, transforming from low-energy folded conformations to high-entropy fully unfolded structures. Our study shows that P3HT is a statistically frustrated system with multiple competing interactions, which complicates fabrication of highly ordered bulk forms but gives structural flexibility of glasses.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available