Crystal Lattice Structures:	Reference Date: 21 Apr 1997
	Last Modified:  5 Sep 2007

The AuCd (B19) Structure

You can now

• see the structure from several perspectives;
• examine the structure with an external viewer; or
• download the coordinates of the atoms in these pictures in XYZ format.
• visualize the structure (Uses the JMOL Applet)

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• When a = b = c, x₁ = ¼, and x₂ = ¾ the atoms are on the sites of a face centered cubic lattice.
• When a = c, x₁ = ¼, and x₂ = ¾ the system reduces to the L1_0 (AuCu) structure.
• When a/b = (8/3)^2/3, c/b = 3^1/2, x₁ = 5/6, and x₂ = 1/3, the atoms are on the sites of an hcp lattice.
• Finally, though it is not obvious from my choice of directions, when x₂ = ½ + x₁ the atoms are at the positions of the alpha Uranium lattice.
• 5 Sept 2007: The Wyckoff positions of the Cd atoms were previously listed as (2d). The actual positions are (2e). The actual coordinates remain correct, so that swaping the positions of the Cd and Au atoms does not change the structure.

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• Prototype: AuCd
• Pearson Symbol: oP4
• Strukturbericht Designation: B19
• Space Group: Pmma (Cartesian and lattice coordinate listings available)
• Number: 51
• Other Compounds with this Structure: AuTi, CdMg, IrMo, IrW, MoRh, NbRh, PdTi, PtTi, PtV
• Primitive Vectors:

  A1	=	a X
  A2	=	b Y
  A3	=	c Z

• Basis Vectors:

  B1	=	+ ¼ A1 + x1 A3	=	+ ¼ aX + x1 cZ	(2e)	(Cd)
  B2	=	- ¼ A1 - x1 A3	=	- ¼ aX - x1 cZ	(2e)	(Cd)
  B3	=	+ ¼ A1 + ½ A2 + x2 A3	=	+ ¼ aX + ½ bY + x2 cZ	(2f)	(Au)
  B4	=	- ¼ A1 - ½ A2 - x2 A3	=	- ¼ aX - ½ bY - x2 cZ	(2f)	(Au)

See these vectors in LaTeX output format.

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Structures indexed by: Strukturbericht Symbol Pearson Symbol Space Group Prototype

This is a mirror of an old page created at the Naval Research Laboratory Center for Computational Materials Science The maintained successor is hosted at http://www.aflowlib.org/CrystalDatabase/ and published as M. Mehl et al., Comput. Mater. Sci. 136 (Supp.), S1-S828 (2017).