Crystal Lattice Structures:	Creation Date: 16 Mar 2003
	Last Modified: 21 Oct 2004

The Si₂U₃ (D5_a) 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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• If we consider the Si₂ dimers as a pseudo-atom, then this is a tetragonal distortion of the Cu₃Au (L1₂) structure.

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• Prototype: Si₂U₃
• Pearson Symbol: tP10
• Strukturbericht Designation: D5_a
• Space Group: P4/mbm (Cartesian and lattice coordinate listings available)
• Number: 127
• Reference: Structure Reports Vol 11, p. 285.
• Primitive Vectors:

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

• Basis Vectors:

  B1	=		0		(U-I)	(2a)
  B2	=	½ A1 + ½ A2	=	½ a X + ½ a Y	(U-I)	(2a)
  B3	=	+ x1 A1 + (½ + x1) A2 + ½ A3	=	+ x1 a X + (½ + x1) a Y + ½ c Z	(U-II)	(4h)
  B4	=	- x1 A1 + (½ - x1) A2 + ½ A3	=	- x1 a X + (½ - x1) a Y + ½ c Z	(U-II)	(4h)
  B5	=	+ (½ + x1) A1 - x1 A2 + ½ A3	=	+ (½ + x1) a X - x1 a Y + ½ c Z	(U-II)	(4h)
  B6	=	+ (½ - x1) A1 + x1 A2 + ½ A3	=	+ (½ - x1) a X + x1 a Y + ½ c Z	(U-II)	(4h)
  B7	=	+ x2 A1 + (½ + x2) A2	=	+ x2 a X + (½ + x2) a Y	(Si)	(4g)
  B8	=	- x2 A1 + (½ - x2) A2	=	- x2 a X + (½ - x2) a Y	(Si)	(4g)
  B9	=	+ (½ + x2) A1 - x2 A2	=	+ (½ + x2) a X - x2 a Y	(Si)	(4g)
  B10	=	+ (½ - x2) A1 + x2 A2	=	+ (½ - x2) a X + x2 a Y	(Si)	(4g)

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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).