The electronic structures and photophysical properties of platinum complexes with C^N^N ligands: the influence of the carborane substituent. Issue 41 (30th September 2015) - Zhang, Wenting
Abstract : Introduction of o -carborane leads to a significant blue-shifted emission band and an obviously-higher electroluminescence efficiency via systemic and in-depth theoretical studies. Abstract : Carboranes have attracted increasing interest in the scientific community due to their remarkable structures and strong electron-withdrawing abilities. In this article, four platinum complexes [(C^N^N)PtCCPh](1 ), [(C^N^N)PtCC-TPA](2 ), [(C^N^N)PtCC-TAB](3 ), [(C^N^N)PtCC-CB](4 ) (where TPA = triphenylamine, TAB = triarylboryl, CB = o -carborane) have been calculated via density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods to mainly explore the influence of carborane substituents on electronic structures, photophysical properties and radiative decay processes. The calculated results reveal that2 with electron-donating triphenylamine has a low radiative decay rate constant and a red-shifted emission band, but3 and4 containing electron-withdrawing triarylboryl and o -carborane exhibit the opposite properties, especially4 is supposed to have the highest phosphorescence quantum yield with the smallest nonradiative decay rate constant. These findings successfully illustrated the structure–property relationship and the designed complex4 with carborane can serve as a highly efficient phosphorescent material in the future.