Functionalized triphenylphosphine oxide-based manganese(<scp>ii</scp>) complexes for luminescent printing
Xiaomeng Huang, Yanyan Qin, Pengfei She, Haixing Meng, Shujuan Liu, Qiang Zhao
Abstract
Three novel neutral manganese(ii) complexes (TPhPONMe2)2MnBr2, (TPhPOOMe)2MnBr2, and (TPhPOCF3)2MnBr2 have been designed and synthesized based on a functionalized Ph3PO ligand. These structures are clarified by single crystal X-ray diffraction analysis, which reveals that they crystallize in centrosymmetric space groups and feature an isolated mononuclear structure with Mn2+ in a tetrahedral environment. The photoluminescence spectra and emission lifetime decay curves of three manganese(ii) complexes show distinct green emission (λem = 498-512 nm) and phosphorescence lifetime (τ = 362.0-663.0 μs). The results of DFT calculations indicate that the energy levels of (TPhPONMe2)2MnBr2 and (TPhPOOMe)2MnBr2 are higher than that of (TPhPOCF3)2MnBr2 due to the electron-donating effect of the NMe2 or OMe group, which explains the blue-shift of the emission wavelength and the increase of emission lifetime. Furthermore, the prepared neutral manganese(ii) complexes can be used for high-resolution luminescent printing.