biostudies-literatureKavanagh SREuropean Research CouncilNational Research Foundation of KoreaEngineering and Physical Sciences Research Council2709-2716https://www.ebi.ac.uk/biostudies/studies/S-EPMC8489399biostudies-literatureUnknown8(10)Perovskite-inspired materials aim to replicate the optoelectronic performance of lead-halide perovskites, while eliminating issues with stability and toxicity. Chalcohalides of group IV/V elements have attracted attention due to enhanced stability provided by stronger metal-chalcogen bonds, alongside compositional flexibility and ns² lone pair cations - a performance-defining feature of halide perovskites. Following the experimental report of solution-grown tin-antimony sulfoiodide (Sn₂SbS₂I₃) solar cells, with power conversion efficiencies above 4%, we assess the structural and electronic properties of this emerging photovoltaic material. We find that the reported centrosymmetric <i>Cmcm</i> crystal structure represents an average over multiple Materials horizonsHidden spontaneous polarisation in the chalcohalide photovoltaic absorber Sn₂SbS₂I₃.PMC8489399EP/R029431EP/S023259/12327795758345EP/T0222132018R1C1B6008728EP/N01572X/1EP/P020194EP/L000202Walsh ASavory CNKavanagh SRScanlon DOfalseHidden spontaneous polarisation in the chalcohalide photovoltaic absorber Sn₂SbS₂I₃.Perovskite-inspired materials aim to replicate the optoelectronic performance of lead-halide perovskites, while eliminating issues with stability and toxicity. Chalcohalides of group IV/V elements have attracted attention due to enhanced stability provided by stronger metal-chalcogen bonds, alongside compositional flexibility and ns² lone pair cations - a performance-defining feature of halide perovskites. Following the experimental report of solution-grown tin-antimony sulfoiodide (Sn₂SbS₂I₃) solar cells, with power conversion efficiencies above 4%, we assess the structural and electronic properties of this emerging photovoltaic material. We find that the reported centrosymmetric <i>Cmcm</i> crystal structure represents an average over multiple 2021-01-01T00:00:00Z2021 Oct2025-05-18T12:31:29.251Z2025-05-18T12:31:29.251ZS-EPMC84893993461754110.1039/d1mh00764e