Time-resolved photoluminescence (PL) and femtosecond transient absorption (TA) spectroscopy are employed to study the photoexcitation dynamics in a highly-emissive two-dimensional perovskite compound (en) 4 Pb 2 Br 9 .3Br with the ethylene diammonium (en) spacer. We find that, while the PL kinetics is substantially T-dependent over the whole range of studied temperatures T ~ 77 -350 K, the PL quantum yield remains remarkably nearly T-independent up to T ~ 280 -290 K appreciably decreasing only

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... t higher temperatures. Considerable differences are also revealed between the TA spectra and responses to the excitation power at low and at room temperatures. Numerical solutions of Onsager-Braun-type kinetic-diffusion equations illustrate that the salient features of the experimental observations are consistent with the picture of a T-dependent dynamic interplay between tightly bound emissive excitons and larger-size, loosely bound, non-emissive geminate charge pairs arising already at earlier relaxation times. The geminate pairs play the role of "reservoir" states providing a delayed feeding into the emitting excitons thus giving rise to the longer-time PL decay components and accounting for a stable PL output at lower temperatures. At higher temperatures, the propensity for thermal dissociation of excitons and bound pairs increases subsequently leading to the precipitous decrease of the PL.