Dual emission from Mn(II) complexes with carbazolyl-substituted phosphoramides

Abstract

The carbazolyl‐substituted phosphoramide N,N,N’,N’‐tetramethyl‐P‐carbazol‐9‐ylphosphonic diamide (L) was successfully coordinated to MnX2 halides (X = Cl, Br, I), obtaining tetrahedral complexes having general formula [MnX2L2]. The structures were ascertained by means of singlecrystal X‐ray diffraction. The three complexes show appreciable luminescence in the visible range upon excitation with UV radiation, attributed to the Mn(II) 4T1(4G)→6A1(6S) transition superimposed to the emission from coordinated ligands. The different contributions are particular evident for the chloro‐complex and the relative intensity depends upon the excitation wavelength. The correlation between the two emitting levels is highlighted by the luminescence decay curves of the three compounds.