@article {2007.04305, archivePrefix = {arXiv}, eprint = {2007.04305}, primaryClass = {cond-mat.str-el}, author = {Darren J Valentine and Dilhan Manawadu and William Barford}, title = {Higher energy triplet-pair states in polyenes and their role in intramolecular singlet fission}, year = {2020}, url = {http://arxiv.org/abs/2007.04305} }