Pd₂Cd11–δ (0.21≤δ≤0.51)–a partly disordered γ-brass type phase and Pd₀.₂₃₈Cd₀.₇₆₂ -a γ-brass related incommensurate phase in the palladium–cadmium system
- CAS Chemical Centre, Lund University, Getingevägen 60, Box 124, Lund SE-22100 (Sweden)
The Cd rich part of the Cd–Pd phase diagram was reassessed by means of synthesis and single crystal and powder X-ray diffraction. The region contains two phases that have been reported to have substantial compositional widths, Cd₁₁Pd₂ and Cd₄Pd. The phase Cd₁₁Pd₂ that has previously been reported to be a disordered γ-brass crystallizing is space group P4-bar 3m is here shown to crystallize in I4-bar 3m and the mechanism for compositional variation is explained. The phase Pd₄Cd has previously been shown to constitute a phase field or a phase bundle of modulated structures and here we determine the structure of a compound Pd₀.₂₃₈Cd₀.₇₆₂ which crystallizes in the orthorhombic superspace group mm(α00)0s0 (F=[(½, ½, 0, 0); (½, 0, ½, 0 ); (0, ½, ½, 0 )] with the fundamental cell dimensions a=4.687(2) Å, b=10.000(1) Å, c=14.140(2) Å, q=0.6432(6)a⁎. - Graphical abstract: The crystal structures of the partly disordered γ-brass type Pd₂Cd11–δ (0.21≤δ≤0.51) and γ-brass related Pd₀.₂₃₈Cd₀.₇₆₂ in the palladium–cadmium binary system. Highlights: • Partly disordered γ-brass type Pd₂Cd11–δ (0.21≤δ≤0.51) and γ-brass related Pd₀.₂₃₈Cd₀.₇₆₂ have been synthesized. • The Pd₂Cd11–δ structure have been described by cluster concept. • Incommensurately modulated Pd₀.₂₃₈Cd₀.₇₆₂ have been described by (3+1) D space description. • The structure of Pd₀.₂₃₈Cd₀.₇₆₂ has two different chains of atomic subunits, each with their own translational periodicities.
- OSTI ID:
- 22306292
- Journal Information:
- Journal of Solid State Chemistry, Vol. 201; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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