A facile synthesis of two new IR optical perovskites based on 1,4-diazabicyclo[2,2,2]octane with a high laser damage threshold

Abstract

The main commercial infrared nonlinear optical (IR NLO) crystals, typically, AgGaS₂, have some inherent disadvantages, for example, low laser damage threshold (LDT) or relatively poor stability, which limit their wide application. Here, we discover two new IR optical perovskites based on 1,4-diazabicyclo[2,2,2]octane, namely, (H₂dabco)(PbCl₃)₂ (1) and (H₂dabco)(H₂PbBr₆)·H₂O (2). 1 and 2 crystallize in the noncentrosymmetric space groups P4₃2₁2 and P6₃mc, respectively, displaying a broad transparent range with high transmission. Particularly, compound 2 exhibits a moderate SHG response of 1.8 times that of KH₂PO₄ (KDP) at 1064 nm with a high laser-induced damage threshold of 328.8 MW cm⁻², indicating that it is a new promising NLO material.