Crystal Lattice Structures:	Reference Date: 29 Jun 1998
	Last Modified: 21 Oct 2004

The Na₃As (D0₁₈) Structure

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• 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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• In Na₃As the internal parameter z is approximately 7/12.
• Removing the Na-I (2b) atoms transforms this structure to MoS₂ (C7).

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• Prototype: Na₃As
• Pearson Symbol: hP8
• Strukturbericht Designation: D0₁₈
• Space Group: P6₃/mmc (Cartesian and lattice coordinate listings available)
• Number: 194
• Primitive Vectors:

  A1	=	½ a X - ½ 3½ a Y
  A2	=	½ a X + ½ 3½ a Y
  A3	=	c Z

• Basis Vectors:

  B1	=	1/3 A1 + 2/3 A2 + ¼ A3	=	½ a X + 12-½ a Y + ¼ c Z	(As)	(2c)
  B2	=	2/3 A1 + 1/3 A2 + ¾ A3	=	½ a X - 12-½ a Y + ¾ c Z	(As)	(2c)
  B3	=	+ ¼ A3	=	+ ¼ c Z	(Na-I)	(2b)
  B4	=	+ ¾ A3	=	+ ¾ c Z	(Na-I)	(2b)
  B5	=	1/3 A1 + 2/3 A2 + z A3	=	½ a X + 12-½ a Y + z c Z	(Na-II)	(4f)
  B6	=	2/3 A1 + 1/3 A2 - z A3	=	½ a X - 12-½ a Y - z c Z	(Na-II)	(4f)
  B7	=	2/3 A1 + 1/3 A2 + (½ + z) A3	=	½ a X - 12-½ a Y + (½ + z) c Z	(Na-II)	(4f)
  B8	=	1/3 A1 + 2/3 A2 + (½ - z) A3	=	½ a X + 12-½ a Y + (½ - z) c Z	(Na-II)	(4f)

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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