Solid state luminescence of CuI and CuNCS complexes with phenanthrolines and a new tris (aminomethyl) phosphine derived from N-methyl-2-phenylethanamine

Abstract

A new tris (aminomethyl) phosphine derived from N-methyl-2-phenylethanamine P(CH2N(CH3)CH2CH2Ph)3 (1) has been synthesized and characterized by the NMR spectra. Also, three new copper(I) iodide or isothiocyanate complexes with 1 1,10-phenanthroline (phen) and 2,9-dimethyl-1,10-phenanthroline (dmp) [CuI(phen)P(CH2N(CH3)CH2CH2Ph)3] (1P) CuI(dmp)P(CH2N(CH3)CH2CH2Ph)3] (1I) and [CuNCS(dmp)P(CH2N(CH3)CH2CH2Ph)3] (1T), have been synthesized and characterized by elemental analysis as well as studied by NMR, UV–vis, IR and luminescence spectroscopies. An X-ray structure of 1P complex revealed that the geometry around Cu(I) center in this complex is distorted pseudo-tetrahedral. Investigated complexes exhibit orange, rather weak photoluminescence in the solid state. This relatively low intensity may be related to the high flattening deformations of the molecular geometries in the excited triplet states On the basis of TDDFT calculations we confirmed that the absorbance and luminescence bands of (MX,MPR3)LCT as well as of (MX)LCT types result mainly from the transitions from the copper–iodine (or isothiocyanate) bonds and a small admixture of copper–phosphine bonds to antibonding orbitals of phen or dmp diimines.