The crystal structure of the binary iridium-aluminum IrAl<sub>2.75</sub> and rhodium-aluminum RhAl<sub>2.63</sub> phase

Zeitschrift fur Kristallographie - Crystalline Materials - Tập 212 Số 6 - Trang 439-444 - 1997
Yu. Grin, K. Peters, U. Burkhardt, K. Gotzmann, M. Ellner

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Abstract The crystal structures of IrAl2.75 (“Ir2Al5”) and RhAl2.63 (“Rh2Al5”) phases have been studied with single crystal methods: space group P23, IrAl2.75, a = 7.674(1) Å, Z = 8, RF = 0.053 (457 hkl, 29 parameters) and RhAl2.63, a = 7.6692(1) Å, RF = 0.042 (684 hkl, 29 parameters). The unit cell contains three transition metal sites and five aluminum sites. Most aluminum sites reveal strong defects in the occupations, some of them are described as being split. The overall number of atoms in the unit cell is 30(1) for IrAl2.75 and 29.0(3) for RhAl2.63. Ordering and full occupation lead either to the AuZn3 (space group Pm[unk]n) or to the hypothetical “Ir4Al13” structure (space group Pm[unk]).

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10.1016/0022-5088(89)90420-7

10.1016/0022-5088(83)90311-9

Edshammar L.-E., Acta Chem. Scand., 21, 647, 10.3891/acta.chem.scand.21-0647

Edshammar L.-E., Acta Chem. Scand., 21, 1104, 10.3891/acta.chem.scand.21-1104a

10.3891/acta.chem.scand.22-2822

Esslinger P., 1957, Z. Metallkd., 48, 126

Ferro R., 1968, Rend., 45, 556

Grin Yu. N., 1994, Z. Kristallogr., 209, 479, 10.1524/zkri.1994.209.6.479

Günzel E., 1958, Z. Metallkd., 49, 234

10.1107/S0365110X65001081

Jung W.-G., 1992, Metall. Trans., 23, 53, 10.1007/BF02654036

Ma L., 1988, Al-Pd and Al-Pt. Scripta Metall., 22, 1791, 10.1016/S0036-9748(88)80286-2

Mahne S., 1996, Z. Kristallogr., 211, 17, 10.1524/zkri.1996.211.1.17

Schubert K., 1959, Z. Metallkd., 50, 534

10.1016/0022-5088(90)90083-V