Crystalline borates are a rich source of diverse optical materials.Here,a rare earth borate fluoride,Sc_(2)F_(2)(B_(2)O_(5)),has been obtained by a conventional hydrothermal reaction.It is unlike other rare earth bora...Crystalline borates are a rich source of diverse optical materials.Here,a rare earth borate fluoride,Sc_(2)F_(2)(B_(2)O_(5)),has been obtained by a conventional hydrothermal reaction.It is unlike other rare earth borate fluorides synthesized under harsh conditions.In the layered structure of Sc_(2)F_(2)(B_(2)O_(5)),ScO_(4)F_(2) octahedra and ScO_(5)F_(2) pentagonal bipyramids connect to each other to form[Sc_(4)O_(10)F_(4)]_(∞) frameworks,which are further linked by B_(2)O_(5)^(4−)anion groups.Specifically,Sc_(2)F_(2)(B_(2)O_(5))does not belong to any types of reported rare earth borate fluoride.More attractively,this compound displays a deep ultraviolet cutoff edge(<200 nm)and very large birefringence(0.19)at 1064 nm based on theoretical calculations.The outstanding birefringence can be seen to originate from the synergistic effect of B_(2)O_(5) and ScO_(n)F_(2) groups when analysed for their polarizability anisotropy-weighted electron density(PAWED).展开更多
基金support from the National Natural Science Foundation of China(22101248)the National Key Laboratory Development Fund(20210002)the Lvyangjinfeng Talent Program of Yangzhou(YZLYJFJH2021YXBS083).
文摘Crystalline borates are a rich source of diverse optical materials.Here,a rare earth borate fluoride,Sc_(2)F_(2)(B_(2)O_(5)),has been obtained by a conventional hydrothermal reaction.It is unlike other rare earth borate fluorides synthesized under harsh conditions.In the layered structure of Sc_(2)F_(2)(B_(2)O_(5)),ScO_(4)F_(2) octahedra and ScO_(5)F_(2) pentagonal bipyramids connect to each other to form[Sc_(4)O_(10)F_(4)]_(∞) frameworks,which are further linked by B_(2)O_(5)^(4−)anion groups.Specifically,Sc_(2)F_(2)(B_(2)O_(5))does not belong to any types of reported rare earth borate fluoride.More attractively,this compound displays a deep ultraviolet cutoff edge(<200 nm)and very large birefringence(0.19)at 1064 nm based on theoretical calculations.The outstanding birefringence can be seen to originate from the synergistic effect of B_(2)O_(5) and ScO_(n)F_(2) groups when analysed for their polarizability anisotropy-weighted electron density(PAWED).
