Affiliation:
1. Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University Beijing 100875 P. R. China
2. Center for Advanced Materials Research Advanced Institute of Natural Sciences Beijing Normal University Zhuhai 519087 P. R. China
Abstract
AbstractNonlinear optical (NLO) switch materials that turn on/off second‐harmonic generation (SHG) at a phase transition temperature (Tc) are promising for applications in the fields of photoswitching and optical computing. However, precise control ofTcremains challenging, mainly because a linearly tunableTchas not been reported to date. Herein, we report a unique selenate, tetragonalP21c[Ag(NH3)2]2SeO4witha=b=8.5569(2) Å andc=6.5208(2) Å that exhibits a strong SHG intensity (1.3×KDP) and a large birefringence (Δnobv.=0.08). This compound forms a series of isostructural solid‐solution crystals [Ag(NH3)2]2SxSe1−xO4(x=0–1.00) that exhibit excellent NLO switching performance and an unprecedented linearly tunablespanning 430 to 356 K. The breaking of localized hydrogen bonds between SeO42−and the cation triggers a phase transition accompanied by hydrogen bond length changes with increasingxand a linear change in the enthalpy.
Funder
National Natural Science Foundation of China