Structural and Optical Properties of Solvated PbI in γ-Butyrolactone: Insight into the Solution Chemistry of Lead Halide Perovskite Precursors.

We employ a fine-tuned theoretical framework, combining molecular dynamics (AIMD), density functional theory (DFT), and time-dependent (TD) DFT methods, to investigate the interactions and optical properties of the iodoplumbates within the low coordinative γ-butyrolactone (GBL) solvent environment, widely employed in the perovskite synthesis. We uncover the extent of GBL coordination to PbI investigating its relation to the solvated PbI optical properties. The employed approach has been further validated by comparison with the experimental UV-vis absorption spectrum of PbI in GBL solvent. A comparison with other solvents, commonly employed in the perovskite synthesis, such as ,-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) is also reported. The methodology developed in this work can be reasonably extended to the investigation of similar systems.