A New Mixed Halide, Cs₂HgI₂Cl₂: Molecular Engineering for a New Nonlinear Optical Material in the Infrared Region

Abstract

A new mixed halide, Cs(2)HgI(2)Cl(2), which contains the highly polar tetrahedron of anion (HgI(2)Cl(2))(2-), has been designed and synthesized by reaction in solution. In its single crystal, the isolated (HgCl(2)I(2))(2-) groups are arranged to form chains. The chains are then further connected into a three-dimensional framework through the Cs atoms that occupy the empty spaces surrounded by halide atoms. All the polar (HgCl(2)I(2))(2-) groups align in such a way that gives a net polarization, leading it to show a phase matchable second harmonic generation (SHG) effect as strong as that of KH(2)PO(4) (KDP) based on the powder SHG measurement. It also displays excellent transparency in the range of 0.4-41 μm with relatively high thermal stability. A preliminary measurement indicates that its laser-induced damage threshold is about 83 MW/cm(2), about twice that of AgGaS(2). This study demonstrates that Cs(2)HgI(2)Cl(2) is a promising nonlinear optical material in the infrared region.

Coexistence of Strong Second Harmonic Generation Response and Wide Band Gap in AZn4Ga5S12 (A=K, Rb, Cs) with 3D Diamond‐like Frameworks

“…Significantly,s uch interesting structural modification not only maintains the 3D DLF structure of the parent structure (namely,a ll the MS 4 (M = Zn/Ga) tetrahedra aligning in the same direction), but also greatlyi ncreasest he E g .T he solidstate diffuse reflectance spectrao ft itle compounds and AGS (as the reference) are shown in Figure 3. [12] Surprisingly,s uch av alue is even greater than some notable IR halideso ro xides, for example, Cs 2 HgCl 2 I 2 (3.15 eV), [36] Pb 17 O 8 Cl 17 (3.44 eV), [37] Pb 2 B 5 O 9 I( 3.10 eV), [38] and Li 2 Ti(IO 3 ) 6 (3.00 eV). [12] Surprisingly,s uch av alue is even greater than some notable IR halideso ro xides, for example, Cs 2 HgCl 2 I 2 (3.15 eV), [36] Pb 17 O 8 Cl 17 (3.44 eV), [37] Pb 2 B 5 O 9 I( 3.10 eV), [38] and Li 2 Ti(IO 3 ) 6 (3.00 eV).…”

“…The experimental E g value of the title compounds is 3.65 eV,w hich is much larger than that of the commercial crystals of AGS (2.58 eV) and comparable to those of the state-of-the-art MIR NLO materials, such as Na 2 ZnGe 2 S 6 (3.25 eV), [22] Na 2 BaSnS 4 (3.27 eV), [15] and LiZnPS 4 (3.44 eV). [12] Surprisingly,s uch av alue is even greater than some notable IR halideso ro xides, for example, Cs 2 HgCl 2 I 2 (3.15 eV), [36] Pb 17 O 8 Cl 17 (3.44 eV), [37] Pb 2 B 5 O 9 I( 3.10 eV), [38] and Li 2 Ti(IO 3 ) 6 (3.00 eV). [39] In addition, the optical transparencies for the title compounds were measured using IR spectra and diffuse-reflectance UV/Vis-NIR spectra and exhibit ac onsiderably broad transparent range (0.40 to 25 mm, Figure S1 in Supporting Information), which is comparablet ot hat of the powdered AGS (0.15 to 23 mm).…”

Lead Mixed Oxyhalides Satisfying All Fundamental Requirements for High‐Performance Mid‐Infrared Nonlinear Optical Materials

“…[40] However,i ti su sually difficult to grow large single crystals with high quality for chalcogenides because of the harsh conditions and laborintensive processes.M eanwhile,h alides were proposed as another promising mid-IR NLO materials. [41] Af ew representative metal halides with wide IR transparent range and considerable LDT include Rb 2 CdBr 2 I 2 , [42] Cs 2 HgI 2 Cl 2 , [43] (Hg 6 P 3 )(In 2 Cl 9 ), [44] Hg 2 BrI 3 , [45] NaSb 3 F 10 , [46] HgBr 2 , [47] and K 2 SbF 2 Cl 3 . [48] Notably,s ome of the crystals can be grown in mild conditions via hydrothermal or solution methods.…”

Beryllium-free Li4Sr(BO3)2 for deep-ultraviolet nonlinear optical applications

“…Over the past decades, continuous intensive studies [4][5][6][7][8][9][10][11] have resulted in the development of various commercial NLO materials, such as b-BaB 2 O 4 (BBO) 12 , LiB 3 O 5 (ref. 13), AgGaS 2 (ref.…”