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Single crystal of a new compound Na2.1Ba0.9Cu0.1Nb4.9O14.3 was synthesised for the first time. The crystal structure has been determined by single crystal X-ray diffraction and the final R value is 0. 0559. The compound crystallizes in a tetragonal unit cell [a = 12. 442(3) A and c = 3. 954 A ]with space growp P4/mbm and Z=2. The compound is in tetragonal tungsten-bronze type structure but some oxygen vacancies exist in the structure. The structure of the compound consists of NbO6 octahedra and octahedra (Nb, Cu)O6 to form triangle, quadrilateral and pentagonal tunnels. The quadrilateral tunnels are occupied by Na atoms. More than 1/2 pentagonal tunnels are occupied by Na atoms and less than 1/2 that are occupied by Ba atoms. Cu2+ replaces Nb5+ to form different-valence isomorpism.
The crystal structure has been determined by single crystal X-ray diffraction and the final R value is 0. 0559. The crystal crystallize a new compound Na2.1Ba0.9Cu0.1Nb4.9O14.3 was synthesized for the first time. in a tetragonal unit cell [a = 12. 442 (3) A and c = 3. 954 A] with space growp P4 / mbm and Z = 2. The compound is in tetragonal tungsten-bronze type structure but some oxygen vacancies exist in The structure of the compound consists of NbO6 octahedra and octahedra (Nb, Cu) O6 to form triangle, quadrilateral and pentagonal tunnels. The quadrilateral tunnels are occupied by Na atoms. More than 1/2 pentagonal tunnels are occupied by Na atoms and less than 1/2 that are occupied by Ba atoms. Cu2 + replaces Nb5 + to form different-valence isomorpism.