Atomic Ordering of Two Neighboring Transition Metals—Cu and Zn from Binary CuZn to Ternary Cu₃ZnSb

Abstract

A new ternary compound CuZnSb was synthesized by high temperature solid state synthesis and characterized by single crystal X-ray diffraction and energy dispersive X-ray analysis. The ternary CuZnSb crystallizes in the tetragonal crystal system with the space group P4/ nmm (129), and its unit cell contains 10 atoms which are distributed over 4 independent crystallographic positions. The structure is built up with [CuSb] slabs that correspond to the unit cells of CuSb and planar 4 nets of Zn atoms. The planar nets of Zn atoms are interspersed between two adjacent [CuSb] slabs. The structure can be viewed as alternating units of CuSb and CsCl type β'-brass (CuZn) structures in the [001]. An unusual atomic ordering of two neighboring transition metals Cu and Zn is observed and is confirmed by first principle calculations. The atomic ordering of Cu and Zn is retained from binary β'-brass structure (CuZn) to ternary CuZnSb. Total energy calculations confirmed the experimental model of Cu/Zn ordering to be the most stable in the structure of CuZnSb. The calculated density of states (DOS) and crystal orbital Hamiltonian population (COHP) explain the stability and bonding characteristics in the structure of CuZnSb. The implication of the persistent Cu/Zn ordering in ternary phases for materials design is emphasized.

Selective Chemical Substitution of Cu in the Structure of TiAl3 Type InPd3: Experimental and Theoretical Studies

“…In Cu 6 Zn 2 Sb 2, unusual atomic ordering between neighbouring Cu and Zn has been observed. At the Zn rich end, two compounds were uncovered where specific chemical substitution of one Cu position (out of two) by Zn was detected [23–24] . Another interesting example of selective substitution was recently reported by Osman and Bobev, where Zn selectively substitutes one of the Li‐positions in Li 15 Ge 4 and forms Li 14 ZnGe 4 [25]…”

“…At the Zn rich end, two compounds were uncovered where specific chemical substitution of one Cu position (out of two) by Zn was detected. [23][24] Another interesting example of selective substitution was recently reported by Osman and Bobev, where Zn selectively substitutes one of the Li-positions in Li 15 Ge 4 and forms Li 14 ZnGe 4 . [25] The importance of specific site preference [22][23][24][25][26][27] in the pseudo-binary/ ternary system motivates us to reinvestigate InPd 3-x Cu x (x = 0-1).…”

“…The importance of specific site preference [22–27] in the pseudo‐binary/ ternary system motivates us to reinvestigate InPd 3‐x Cu x (x=0–1). In this report, the InPd 3‐x Cu x (x=0–1) were synthesized by conventional high temperature method, and crystal structures were reinvestigated by single crystal and powder X‐ray diffraction and first‐principles electronic structure calculations.…”

“…[23][24] Another interesting example of selective substitution was recently reported by Osman and Bobev, where Zn selectively substitutes one of the Li-positions in Li 15 Ge 4 and forms Li 14 ZnGe 4 . [25] The importance of specific site preference [22][23][24][25][26][27] in the pseudo-binary/ ternary system motivates us to reinvestigate InPd 3-x Cu x (x = 0-1). In this report, the InPd 3-x Cu x (x = 0-1) were synthesized by conventional high temperature method, and crystal structures were reinvestigated by single crystal and powder X-ray diffraction and first-principles electronic structure calculations.…”

Selective Chemical Substitution in Intermetallic Compounds: DFT Study of Two Representative Cases: Cu5Zn3Sb2 and InPd2Cu

“…The ordering between the neighboring Cu and Zn atoms in Cu3ZnSb is remarkable, and it is one of the rarest examples of ordering between Cu and Zn in ternary intermetallic compounds. Interestingly, the ordering present in binary CuZn and Cu2Sb is retained in Cu3ZnSb [7][8].…”