2023 Prize Winner - Roslyn Forecast

Roslyn’s interest in light-emitting materials began when she was completing her M.Sc. in Nanoscience at Lund University in Sweden. After a diverse career of teaching maths and physics in Denmark and Australia, and stints at The Office of the Chief Scientist for Australia and IP Australia, she decided to embark upon the Ph.D. journey at RMIT University in the Australian Centre for Excellence in Exciton Science with Professor Jared H. Cole.

Roslyn’s research focused on photochemical upconversion, a process which pools the energy of two (or more) photons as a molecular excitation, and then emits one higher energy photon. Upconversion is a promising means of utilising incoming solar irradiance below the silicon bandgap and surpassing the efficiency limit of conventional crystalline silicon solar cells.

In triplet–triplet annihilation upconversion in solution, the absorbed photons produce excited molecular triplet states, which as they diffuse through the fluid may collide and annihilate to produce one molecular singlet state that fluoresces. As triplet–triplet annihilation is a spin-selective process, it exhibits a magnetic field response, which has traditionally been described and modelled in the context of Atkins and Evans’ theory. Roslyn’s work reformulated the theory using a modern open quantum systems approach, corrected, and extended it to describe not only the fluorescent singlet state, but also the optically dark triplet and quintet spin manifolds.

Roslyn completed her PhD thesis in 2023 and is now employed in the School of Physics at Melbourne University as an education-focused academic.

The Ian Snook Prize has assisted Roslyn in attending international physics conferences and promoting her work on spin-mediated effects in photochemical upconversion. Throughout her PhD, Roslyn published three first-author papers, and was a contributing author on another:

Forecast, R.; Campaioli, F.; Cole, J. H. “Magnetic Field Effects in Triplet– Triplet Annihilation Upconversion: Revisiting Atkins and Evans’ Theory” J. Chem. Theory Comput. 2023, 19, 7816-7824, Editors’ Choice.

Forecast, R.; Gholizadeh, E. M.; Prasad, S. K. K.; Blacket, S.; Tapping, P. C.; McCamey, D. R.; Tayebjee, M. J. Y.; Huang, D. M.; Cole, J. H.; Schmidt, T. W. “Power Dependence of the Magnetic Field Effect on Triplet Fusion: A Quantitative Model” J. Phys. Chem. Lett. 2023, 14, 4742–4747.

Forecast, R.; Campaioli, F.; Schmidt, T. W.; Cole, J. H. “Photochemical Up- conversion in Solution: The Role of Oxygen and Magnetic Field Response” J. Phys. Chem. A 2023, 127, 1794–1800.

Dvořák, M.; Prasad, S. K. K.; Dover, C. B.; Forest, C. R.; Kaleem, A.; MacQueen, R. W.; Petty, A. J.; Forecast, R.; Beves, J. E.; Anthony, J. E.; et al. “Singlet Fission in Concentrated TIPS-Pentacene Solutions: The Role of Excimers and Aggregates” J. Am. Chem. Soc. 2021, 143, 13749–13758.