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Eu(III) and Yb(III) complexes with the carbazole-dipicolinato ligand dpaCbz(2−), namely K(3)[Eu(dpaCbz)(3)] and K(3)[Yb(dpaCbz)(3)], were isolated. The Eu(III) complex displayed metal-centred emission upon one-photon excitation with a sensitized emission efficiency [Formula: see text] of 1.8±0.3 %, corresponding to an intrinsic emission efficiency [Formula: see text] of 46% and a sensitization efficiency of η(sens) 3.9%, with an emission lifetime of the emissive state τ of 1.087±0.005 ms. The Yb(III) complex displayed [Formula: see text] of 0.010±0.001 %, and a τ of 2.32±0.06 μs. The Eu(III)-centred emission was sensitized as well upon two-photon excitation and a two-photon absorption cross-section σ(2PA) of 63 GM at 750 nm was determined for the complex. The one- or two-photon sensitized emission intensity of the Eu(III) complex changes by more than two-fold when the solvent viscosity is varied in the range 0.5 – 200 cP and the emission is independent of dissolved oxygen. The Yb(III) complex displays a change in emission intensity as well. However, in this case, a dependence of the emission intensity on dissolved oxygen content was observed.