AXHg₃P₂S₈ (A = Rb, Cs; X = Cl, Br): New Excellent Infrared Nonlinear Optical Materials with Mixed‐Anion Chalcohalide Groups of Trigonal Planar [HgS₂X]³⁻ and Tetrahedral [HgS₃X]⁵⁻

Abstract

A series of nonlinear optical (NLO) chalcohalides AXHg3P2S8 (A = Rb, Cs; X = Cl, Br), which contain various Hg‐based building units including mixed‐anion trigonal planar [HgS2X]3− and tetrahedral [HgS3X]5−, are successfully synthesized. These compounds display good water resistance, wide infrared transparent region (0.42–17 µm), high laser‐induced damage thresholds (4.5–6 × AgGaS2), and strong phase‐matchable second harmonic generation (SHG) response close to AgGaS2. The mixed‐anion chalcohalide groups serving as functional building units in NLO materials are studied for the first time and proven to be very effective. This work opens a new avenue for new NLO material design to achieve the balance between strong SHG efficiency and large bandgap.

Highly Distorted [HgS4] Motif-Driven Structural Symmetry Degradation and Strengthened Second-Harmonic Generation Response in the Defect Diamond-Like Chalcogenide Hg3P2S8

“…The former may be caused by residual mineral oil on the surface of the crystal sample, and the latter are possibly caused by multi-phonon absorption. A similar phenomenon is also found in the IR transmission spectrum of single-crystal CuZnPS 4 and AXHg 3 P 2 S 8 19,46. Moreover, the Raman spectrum (FigureS3) of Hg 3 P 2 S 8 indicates that its absorption edge is near 600 cm −1 , which is also in good agreement with the IR transmittance spectra.…”

Structural modification from centrosymmetric Rb4Hg2Ge2S8 to noncentrosymmetric (Na3Rb)Hg2Ge2S8: mixed alkali metals strategy for infrared nonlinear optical material design

“…3a), which is comparable to that of previously reported IR NLO materials Na 2 Hg 3 Si 2 S 8 (1.3 × AgGaS 2 ), 34 BaHgSe 2 (1.5 × AgGaS 2 ), 14 and CsBrHg 3 P 2 S 8 (1.2 × AgGaS 2 ). 58 The curve of SHG response with particle size is shown in Fig. 3b, indicating that (Na 3 Rb)Hg 2 Ge 2 S 8 is not phase-matched.…”

Rational design of a promising oxychalcogenide infrared nonlinear optical crystal

“…Similar measurements have also been found in the previous research. [34][35][36][37] It is clear that there is no obvious absorption in the range from 1800 to 800 cm À1 , corresponding to 5.5 to 12.5 mm (Fig. 2a).…”