3D Chiral Metal Halide Semiconductors
Marco Moroni, Luca Gregori, Clarissa Coccia, Massimo Boiocchi, Marta Morana, Doretta Capsoni, Andrea Olivati, Antonella Treglia, Giulia Folpini, M. Patrini, Isabel Gonçalves, Heyong Wang, Chiara Milanese, Annamaria Petrozza, Edoardo Mosconi, Filippo De Angelis, Lorenzo Malavasi
Abstract
High Resolution Image Download MS PowerPoint Slide Chiral metal halides are promising materials for nonlinear optics and spin-selective devices. Typically, chirality is introduced via large chiral organic cations, leading to low-dimensional structures and limitations in charge transport. Here, we design a family of chiral metal halides based on the relatively small ditopic R / S -3-aminoquinuclidine (3-AQ) cation, forming an ( R / S -3AQ)Pb 2 Br 6 structure closely related to the 3D corner-sharing octahedral network of perovskites. The resulting material exhibits a direct bandgap, isotropic band structure, and fully 3D photoexcitation. Circular dichroism confirms a chiral anisotropy factor consistent with theoretical predictions. Moreover, the material displays a Rashba effect in the conduction band, which is attributed to spin–orbit coupling and the lack of inversion symmetry. Offering rich chemical tunability and efficient 3D charge transport, this new class of chiral semiconductors provides a promising platform for advancing nonlinear optoelectronic and spintronic devices.