A new thio-germanium sulfide Li2Ga2GeS6 has been synthesized for the first time and its structure was found to be isomorphous with AgGaGeS4, which is well-known as a promising infrared NLO material. The host structure is built of GaS4 tetrahedra linked by corners to GeS4 tetrahedra to create a 3D framework forming tunnels along the c-axis, in which the Li+ions are located. The second harmonic generation (SHG) efficiency determined on powders of Li2Ga2GaS6 is 200 times larger than that of α-SiO2. Unlike AgGaS2 and AgGaGeS4, Li2Ga2GeS6 was observed to be very stable under prolonged Nd:YAG 1.064 μm laser pumping, indicative of a large improvement in laser damage threshold. This new material could supplant Ag phases in the next generation of high-power infrared NLO applications.
Disciplines
Atomic, Molecular and Optical Physics | Inorganic Chemistry | Materials Chemistry | Materials Science and Engineering
CommentsReprinted with permission from Chemistry of Materials 20 (2008) ReceiVed March 12, 2008. ReVised Manuscript ReceiVed July 8, 2008 A new thio-germanium sulfide Li 2 Ga 2 GeS 6 has been synthesized for the first time and its structure was found to be isomorphous with AgGaGeS 4 , which is well-known as a promising infrared NLO material. The host structure is built of GaS 4 tetrahedra linked by corners to GeS 4 tetrahedra to create a 3D framework forming tunnels along the c-axis, in which the Li + ions are located. The second harmonic generation (SHG) efficiency determined on powders of Li 2 Ga 2 GaS 6 is ∼200 times larger than that of R-SiO 2 . Unlike AgGaS 2 and AgGaGeS 4 , Li 2 Ga 2 GeS 6 was observed to be very stable under prolonged Nd:YAG 1.064 µm laser pumping, indicative of a large improvement in laser damage threshold. This new material could supplant Ag phases in the next generation of high-power infrared NLO applications.