Hg2(SeO3)(TeO3): a novel tellurite–selenite birefringent crystal achieved by assembling multiple functional groups

Abstract

Birefringent crystals are essential components in modern optical devices. Exploring new material systems capable of serving as birefringent materials is of great significance for the advancement of optical technology. In this study, we propose a method to enhance the birefringence of compounds through the assembly of multiple functional groups. For the first time, we combined Hg²⁺, (SeO₃)²⁻, and (TeO₃)²⁻ groups to successfully synthesize a new compound, Hg₂(SeO₃)(TeO₃). This compound exhibits a birefringence of 0.097@546 nm, along with excellent thermal stability up to 420 °C and a broad transmission window from 0.32 to 6.3 μm. Notably, Hg₂(SeO₃)(TeO₃) is the first Hg-based tellurite–selenite birefringent crystal to date. Our research not only confirms the potential of tellurite–selenite systems in the field of birefringent materials, but also opens up new possibilities for the development of future optical materials.