1 Electronic Supplementary Information for: Visible light-harvesting trans bis(alkylphosphine) Platinum(II)-alkynyl complexes showing long-lived triplet excited states as triplet photosensitizers for triplet-triplet annihilation upconversion Lianlian Liu, a Dandan Huang, a Sylvia M. Draper, b Xiuyu Yi, a Wanhua Wu a and Jianzhang Zhao* a a State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 West Campus, 2 Ling Gong Road, Dalian 116024, P. R. China. b School of Chemistry, University of Dublin, Trinity College, Dublin 2, Ireland. Phone/Fax: +86 411 8498 6236 (J. Z.) E-mail: zhaojzh@dlut.edu.cn (J. Z.) web: http://finechem.dlut.edu.cn/photochem (J. Z.) Table of Contents 1.0 NMR and HRMS spectra.... ………………………………………………………………………………...... …..3 2.0 Emission spectra.... …………………………..... ………………………………………………………………17 3.0 Transient absorption details……………………...…………………………………………………………….18 4.0 TTA upconversion details……………………………….………………………………………………........... 19 5.0 Photosensitizing of 1 O 2 ……………….…………......... ………………………………………………….......... 25 6.0 DFT caculations……….……………......... ………………………………………………………........... 28 7.0 The coordinates of the optimized ground state geometries of complexes..………………………..........31 8.0 The coordinates of the optimized triplet state geometries of complexes……….…………………….……40 Electronic Supplementary Material (ESI) for Dalton Transactions This journal is © The Royal Society of Chemistry 2013