Synthesis and characterization of Cu[sub 3]NbSe[sub 4] and KCu[sub 2]TaSe[sub 4]

Journal Article · Mon Nov 01 04:00:00 EST 1993 · Journal of Solid State Chemistry; (United States)

OSTI ID:7207451

Lu, Ying-Jie; Ibers, J A ^[1]

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1. Northwestern Univ. Evanston, IL (United States)

Cu[sub 3]NbSe[sub 4] has been synthesized from a stoichiometric reaction of the elements at 950[degrees]C. The material, which has the sulvanite (Cu[sub 3]VS[sub 4]) structure, crystallizes in space group T[sup 1[sub d]]-P[bar 4]3m of the cubic system with one formula unit in a cell with a = 5.638(1) [angstrom] at -165[degrees]C. Cu[sub 3]NbSe[sub 4] has a three-dimensional structure with edge-sharing of CuSe[sub 4] and NbSe[sub 4] tetrahedra and corner-sharing among CuSe[sub 4] tetrahedra extending equally in all directions. KCu[sub 2]TaSe[sub 4] was prepared from a reaction of K[sub 2]Se[sub 5], Cu, Ta, and Se in the ratio 1:4:2:3 at 850[degrees]C. KCu[sub 2]TaSe[sub 4] crystallizes in space group C[sup 4][sub s]-Cc of the monoclinic system with four formula units in a cell of dimensions a = 5.660(1), b = 18.829(4), c = 7.662(2) [angstrom], [beta] = 90.04(3)[degrees] at -165[degrees]C. In this structure the Ta and two independent Cu atoms are in tetrahedral sites. The CuSe[sub 4] and TaSe[sub 4] tetrahedra share edges and corners to make up two-dimensional layers. These layers are separated from one another by K[sup +] ions. KCu[sub 2]TaSe[sub 4] is not isostructural with KCu[sub 2]NbSe[sub 4], although the structures are similar.

• OSTI ID: 7207451
• Journal Information: Journal of Solid State Chemistry; (United States), Journal Name: Journal of Solid State Chemistry; (United States) Vol. 107:1; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
ALKALI METAL COMPOUNDS
CHALCOGENIDES
CHEMICAL PREPARATION
COPPER COMPOUNDS
COPPER SELENIDES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CUBIC LATTICES
LATTICE PARAMETERS
MONOCLINIC LATTICES
NIOBIUM COMPOUNDS
NIOBIUM SELENIDES
POTASSIUM COMPOUNDS
POTASSIUM SELENIDES
REFRACTORY METAL COMPOUNDS
SELENIDES
SELENIUM COMPOUNDS
SYNTHESIS
TANTALUM COMPOUNDS
TANTALUM SELENIDES
TRANSITION ELEMENT COMPOUNDS