Tracing Chirality Across Length Scales in Organic Semiconductors

Title: Tracing Chirality Across Length Scales in Organic Semiconductors

Speaker: Dr Rishi Shivhare

Abstract: Symmetry breaking provides a powerful strategy for uncovering new material properties, with chirality offering a compelling example in organic semiconductors. In this seminar, I will discuss how chirality introduced through molecular dopants can propagate across length scales - from local changes in polymer conformation to supramolecular organisation, ultimately producing an amplified chiroptical response. Using polyfluorene-based systems, I will show how complementary spectroscopy and molecular modelling reveal the structural origins of chirality transfer and the role of polymer conformation in sustaining helical organisation. I will conclude by outlining ongoing work at the University of Sydney using polarisation-resolved spectroscopy to investigate how molecular symmetry breaking influences the excited-state, optical and magneto-optical properties of chiral materials.

Bio: Dr. Rishi Shivhare is a Lecturer in the School of Chemistry at the University of Sydney, where he has been based since August 2025. He completed his Master’s degree at the Indian Institute of Science, Bengaluru, before undertaking his PhD at the Technical University of Dresden in Germany. Following his PhD, he conducted postdoctoral research at the University of Bern as an FP-RESOMUS Fellow (Marie Skłodowska-Curie Actions) and later at the University of Hasselt. His research experience across Germany, Switzerland and Belgium has spanned organic photovoltaics, ultrafast spectroscopy, molecular semiconductors and chiral optoelectronic materials. His current work explores how molecular structure, symmetry and supramolecular organisation govern the optical and excited-state properties of organic materials, with a particular focus on chiral semiconductors, polarisation-resolved spectroscopy and emerging photonic technologies.