BaLiTe2O5X (X = Cl, Br): mixed alkali/alkaline-earth metal tellurite halides with [Te2O5]∞ chains.
Dalton Trans
; 49(15): 4914-4919, 2020 Apr 15.
Article
in En
| MEDLINE
| ID: mdl-32232276
ABSTRACT
Isostructural mixed alkali/alkaline-earth metal tellurite halides BaLiTe2O5X (X = Cl, Br) have been successfully synthesized by a mild hydrothermal method, which possess the [Te2O5]∞ chains formed by the corner-sharing connections of the TeO3 and TeO4 polyhedra. The [Te2O5]∞ chains are bridged via the LiO3 polyhedra to form the [LiTe2O5]∞ layers with 4- and 6-membered rings. The adjacent [LiTe2O5]∞ layers are linked via the BaO9 polyhedra to form the [BaLiTe2O5]∞ double layers, which are further connected via weak Ba-X-Li interactions to generate a 3D framework. Analysis of different lithium tellurites shows that the different arrangements of the Te-O and Li-O units in the lithium tellurites can be attributed to the cation-cation repulsion and lone-pair effect. Both compounds display good thermal stability, wide optical bandgaps (4.25 and 4.13 eV), and large birefringence. First-principles calculations indicate that the TeOn groups and X- determine the optical properties of BaLiTe2O5X (X = Cl, Br).
Full text:
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Dalton Trans
Year:
2020
Document type:
Article