From CdPb8(SeO3)4Br10 to Pb3(TeO3)Br4: the first tellurite bromide exhibiting an SHG response and mid-IR transparency

Abstract

Herein, we report two new selenite/tellurite bromide compounds, namely, CdPb₈(SeO₃)₄Br₁₀ and Pb₃(TeO₃)Br₄. The former crystallized in a centrosymmetric space group, while the latter is a non-centrosymmetric compound. Specifically, CdPb₈(SeO₃)₄Br₁₀ demonstrates high thermal stability (425 °C) and a wide optical transparency window (0.33–6.5 μm), while Pb₃(TeO₃)Br₄ exhibits an second harmonic generation response approximately equivalent to that of KDP, appropriate birefringence (0.095@532 nm and 0.066@1064 nm), wide optical transparency window (0.33–6.5 μm) and high thermal stability (522 °C). These results indicated that lead tellurite bromides could be promising nonlinear optical material systems in the mid-IR wavelength.