Dissymmetry Factor Enhancement: A Data-Driven Approach to Unravel the Synthesis Knobs of Chiral 2D Perovskites

Chiral 2D metal halide perovskites (MHPs) hold promise for next-generation spin-optoelectronic applications. While still in early-stage development, significant efforts have focused on optimizing the dissymmetry factor (g), particularly in terms of their circular dichroism (gabs), which quantifies the chiroptical response and is related to spin-polarized optical properties in chiral systems. These materials typically exhibit intrinsically low gabs values (10E-3), with variations spanning two orders of magnitude due to co-dependent structural, morphological, and experimental factors. Here, Pearson correlation analysis identified solvent choice as the primary factor governing gabs variability in chiral 2D MHP thin films based on R-/S-𝛼-methylbenzylammonium. Subsequently, a combination of Pearson correlation, ANOVA, and Gaussian Process Regression revealed that, for acetonitrile-based samples, strain, film thickness, and annealing temperature are the key parameters for optimizing gabs. In contrast, films prepared with higher boiling point solvents exhibit a more complex interdependence of gabs with film texture and excitonic integral intensity. The statistical analysis of the synthesis-chiroptical property relationship provides a foundation for the rational design of chiral 2D MHPs, while also guiding the exploration of alternative chiral cations, compositions, and deposition strategies.