(38.9%) followed by the one with x=0.25 (34%). The possible origin of the emission intensity recover at low-T is still under investigation, but we expect an influence of the temperature on the compound distortion degree and, in addition, low temperature would also contribute to reduce thermal activated exciton hopping, with both these phenomena in turn affecting the selftrapping exciton deactivation processes, as recently reported for analogous two-dimensional tin halide perovskites. To summarize, the investigation of the novel DA2Ge(Br1-xIx)4 system revealed: i) the formation of a continuous solid solution along with halide alloying with orthorhombic symmetry; ii) the presence of a relevant discontinuity (contraction) in the long c-axis variation passing from Br-rich to I-rich samples; iii) the variation of the band gap from about 2.74 eV (DA2GeBr4) to 2.17 eV (DA2GeI4) with a different slope as a function of x corresponding to the two regimes of c-axis trend; iv) a very similar RT PL with negligeable emission for Br-rich samples which progressively increases along with the increase in the I-content; and v) an enhancement of PL intensity, narrowing of the peaks, and increase of the τ values by reducing the temperature, with mixed compositions showing the highest QYs.