New Luminescent Lanthanide Tetrakis-Complexes NEt4[LnL(4)] Based on Dimethyl-N-Benzoylamidophosphate

New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt4[LnL(4)] (Ln(3+)=La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt4+ on the structure and properties of the tetrakis-complex [LnL4](-) is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of D-5(0)-> F-7(4) transition, observed in the luminescence spectrum of NEt4[EuL4], is discussed based on theoretical calculations.