Obtaining sulfate-based materials with large birefringence is of great challenge due to the weak polarizability anisotropy of the constituting spherical SO_(4)^(2-)tetrahedron.Here,we have implemented a polyhedron of ...Obtaining sulfate-based materials with large birefringence is of great challenge due to the weak polarizability anisotropy of the constituting spherical SO_(4)^(2-)tetrahedron.Here,we have implemented a polyhedron of stereoactive lone pair cations,IO_(3)-to the system to tackle the issue.Centimetre-sized single crystals of an alkali metal sulfate iodate,K_(2)SO_(4)·HIO_(3),have been readily grown by an accessible solution-evaporation method.Optical measurements on K_(2)SO_(4)·HIO_(3)single crystals reveal that the reported material exhibits a 70-fold increase in birefringence(ca.0.14 at 589.3 nm)compared to that of the singular sulfate,K_(2)SO_(4).In addition,K_(2)SO_(4)·HIO_(3)exhibits a blue-shifted UV cutoff edge of 275 nm,25 nm shorter than that ofα-HIO_(3),highlighting the key role of the SO_(4)^(2-)tetrahedron in broadening the transmittance window.展开更多
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(grant no.2018R1A5A1025208 and 2019R1A2C3005530).
文摘Obtaining sulfate-based materials with large birefringence is of great challenge due to the weak polarizability anisotropy of the constituting spherical SO_(4)^(2-)tetrahedron.Here,we have implemented a polyhedron of stereoactive lone pair cations,IO_(3)-to the system to tackle the issue.Centimetre-sized single crystals of an alkali metal sulfate iodate,K_(2)SO_(4)·HIO_(3),have been readily grown by an accessible solution-evaporation method.Optical measurements on K_(2)SO_(4)·HIO_(3)single crystals reveal that the reported material exhibits a 70-fold increase in birefringence(ca.0.14 at 589.3 nm)compared to that of the singular sulfate,K_(2)SO_(4).In addition,K_(2)SO_(4)·HIO_(3)exhibits a blue-shifted UV cutoff edge of 275 nm,25 nm shorter than that ofα-HIO_(3),highlighting the key role of the SO_(4)^(2-)tetrahedron in broadening the transmittance window.
