Crystal Lattice Structures:	Creation Date: 26 Aug 1998
	Last Modified: 13 Dec 2005

The γSe (A8) Crystal 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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• Donohue refers to this as the α Se structure, calling α Se and β Se ``monoclinic α'' and ``monoclinic β,'' respectively.
• When x = 1/3 this reduces to the A_i (β Po) or A10 (α Hg) structure.
  • If, in addition, c = 6^1/2 a, then the structure becomes fcc (A1).
  • On the other hand, if c = (3/2)^1/2 a, then the structure becomes simple cubic (A_h).

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• Prototype: γSe
• Pearson Symbol: hP3
• Strukturbericht Designation: A8
• Space Group: P3₁21 (Cartesian and lattice coordinate listings available)
• Number: 152
• Reference: Villars and Calvert, Pearson's Handbook, vol. IV, 5215.
• Other Systems with this Structure: Te, SeTe, Se₃Te
• Primitive Vectors:

  A1	=	½ a X - ½ 31/2 a Y
  A2	=	½ a X + ½ 31/2 a Y
  A3	=	c Z

• Basis Vectors:

  B1	=	x A1 + 1/3 A3	=	½ a x X - ½ 31/2 a x Y + 1/3 c Z	(Se)	(3a)
  B2	=	x A2 + 2/3 A3	=	½ a x X + ½ 31/2 a x Y + 2/3 c Z	(Se)	(3a)
  B3	=	-x A1 - x A2	=	- a x X	(Se)	(3a)

See these vectors in LaTeX output format.

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Structures indexed by: Strukturbericht Symbol Pearson Symbol Space Group Prototype

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