论文信息 - REFINEMENT OF THE CRYSTAL-STRUCTURE OF TETRAGONAL AL2CU

REFINEMENT OF THE CRYSTAL-STRUCTURE OF TETRAGONAL AL2CU

Abstract New single-crystal X-ray diffraction data have been obtained for the θ-phase of aluminum-copper (Al2Cu). Results of the refinement are presented. The structure is found to be in accordance with the one determined by J. B. Friauf (J. Amer. Chem. Soc. 49, 3107–3114 (1927)) . The compound crystallizes in the tetragonal space group I4 mcm (No. 140) with a unit cell of dimensions a = 6.067(1) and c = 4.877(1) A. There are four formula-units per unit cell. A full-matrix least-squares refinement with 237 observed reflections and 8 parameters converged to RF = 0.032 (wR = 0.037). In addition to more accurate values for the lattice parameters and the atomic coordinates, anisotropic temperature factors are obtained.

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