# Engineering the Electronic Structure and Optoelectronic Properties of Chiral Metal Halides through Cation Design

## TL;DR

This paper explores how designing specific cations can control the electronic and optical properties of chiral metal halides for optoelectronic applications.

## Contribution

A new chiral cation with amino and hydroxyl groups enables synthesis of enantiopure metal halides with tunable electronic and chiroptical properties.

## Key findings

- The new cation allows synthesis of enantiopure (S/R-AMOL)SnI3 and (S/R-AMOL)PbI3 with distinct structural and bonding features.
- Sn and Pb analogues show significant differences in electronic structure, chiroptical properties, and exciton binding energy.
- Hydroxyl-bearing chiral centers effectively transfer chirality and influence optoelectronic behavior.

## Abstract

The tunability of hybrid organic–inorganic metal
halides
through targeted chemical design is one of their most attractive features,
enabling fine control over physical properties for optoelectronic
applications. In chiral systems, where chirality is introduced via
organic amines, this tunability is often limited by the scarcity of
suitable chiral cations. In this study, we report a family of 1D lead-
and tin-based chiral hybrid halides incorporating a tailor-made cation
bearing both amino and hydroxyl functional groups. This chiral ligand
enables the synthesis of enantiopure (S/R-AMOL)­SnI3 and (S/R-AMOL)­PbI3, where S/R-AMOL stands for (2S,2′S)-1,1′-azanediylbis­(butan-2-ol) or (2R,2′R)-1,1′-azanediylbis­(butan-2-ol).
These compounds exhibit distinctive structural arrangements and bonding
interactions, demonstrating effective chirality transfer through chiral
centers bearing hydroxyl groups. Remarkably, substantial differences
in the electronic structure and chiroptical properties are observed
between the Sn and Pb analogues, including variations in emission
characteristics, exciton binding energy, and orbital contributions
to the electronic structure.