Three new ytterbium complexes of the general formula [YbL 2 Cl 3 ] with expanded aromatic N-donor based ligands based on 1,10-phenanthroline (dipyrido-[3,2-f : 2',3'-h]-quinoxaline (DPQ), 2-methyldipyrido-[3,2-f : 2',3'-h]-quinoxaline (MeDPQ) and 1,10-phenanthroline (Phen)) were synthesized and characterized using different structural analysis, simultaneous thermal analysis, and photoluminescence, and UV-Vis-NIR spectroscopy. The compounds were obtained by the reaction of ytterbium(III) chloride hexahydrate and the corresponding aromatic N-donor through substitution of water from the coordination sphere with the organic ligand. Photoluminescence studies revealed Yb 3 + -based NIR emission of the corresponding compounds with following luminescence lifetimes [Yb(DPQ) 2 Cl 3 ] (1) -7.8(1) μs, [Yb(MeDPQ) 2 Cl 3 ] (2) -9.3(1) μs, [Yb(Phen) 2 Cl 3 ] (3) -8.7(1) μs. The resulting complexes are stable under atmospheric conditions, exhibit good thermal stability, and start to oxidize only at sufficiently high temperatures: (1) at 470 °C, (2) at 430 °C, and (3) at 395 °C.