Giant Optical Anisotropy in a Covalent Molybdenum Tellurite via Oxyanion Polymerization.
Adv Sci (Weinh)
; 11(12): e2306670, 2024 Mar.
Article
in En
| MEDLINE
| ID: mdl-38288532
ABSTRACT
Large birefringence is a crucial but hard-to-achieve optical parameter that is a necessity for birefringent crystals in practical applications involving modulation of the polarization of light in modern opto-electronic areas. Herein, an oxyanion polymerization strategy that involves the combination of two different types of second-order Jahn-Teller distorted units is employed to realize giant anisotropy in a covalent molybdenum tellurite. Mo(H2O)Te2O7 (MTO) exhibits a record birefringence value for an inorganic UV-transparent oxide crystalline material of 0.528 @ 546 nm, which is also significantly larger than those of all commercial birefringent crystals. MTO has a UV absorption edge of 366 nm and displays a strong powder second-harmonic generation response of 5.4 times that of KH2PO4. The dominant roles of the condensed polytellurite oxyanions [Te8O20]8- in combination with the [MoO6]6- polyhedra in achieving the giant birefringence in MTO are clarified by structural analysis and first-principles calculations. The results suggest that polymerization of polarizability-anisotropic oxyanions may unlock the promise of birefringent crystals with exceptional birefringence.
Full text:
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Adv Sci (Weinh)
Year:
2024
Document type:
Article