Unraveling the Role of Structural Topology on Chirality Transfer and Chiroptical Properties in Chiral Germanium Iodides

Chiral hybrid organic–inorganic metal halides are highly promising chiroptoelectronic materials with potential applications in several fields, such as circularly polarized photodetectors, second-order nonlinear optics, and spin-selective devices. However, the ability of manipulating the chiroptical response and the chirality transfer from the organic ligands require one to shed light on structure–property correlations. Herein, we devised and prepared two novel Ge-based chiral hybrid organic–inorganic metal halides showing a different structural topology, namely, a 1D and a 2D arrangement, but composed of the same chemical building blocks: (R/S-ClMBA)3GeI5 and (R/S-ClMBA)2GeI4. Through a combined experimental and computational investigation on these samples, we discuss the impact of structural dimensionality on chiroptical properties, chirality transfer, and spin-splitting effects; also, we highlight the impact of structural distortions. The approach presented here paves the way for a solid understanding of the factors affecting the properties of chiral metal halides, thus allowing a future wise materials engineering.