Citation: Murgatroyd, Philip A. E.; Smiles, Matthew J.; Savory, Christopher N.; Shalvey, Thomas P.; Swallow, Jack E. N.; Fleck, Nicole; Robertson, Craig M.; J\"ackel, Frank; Alaria, Jonathan; Major, Jonathan D.; Scanlon, David O.; Veal, Tim D. (2020). GeSe: Optical Spectroscopy and Theoretical Study of a van der Waals Solar Absorber. Chemistry of Materials, , pp. -.