Crystal Lattice Structures:	Reference Date:  1 Sep 1995
	Last Modified: 17 Feb 2007

The HCP (A3) 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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• Prototype: Mg
• Pearson Symbol: hP2
• Strukturbericht Designation: A3
• Space Group: P6₃/mmc (Cartesian and lattice coordinate listings available)
• Number: 194
• Other Elements with this Structure: Be, Sc, Ti, Co, Zn, Y, Zr, Tc, Ru, Cd, Gd, Tb, Dy, Ho, Er, Tm, Lu, Hf, Re, Os, Tl
• Reference: Ashcroft and Mermin, p. 77.
• 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	=	1/3 A1 + 2/3 A2 + ¼ A3	=	½ a X + ½ 3-1/2 a Y + ¼ c Z	(Mg)	(2c)
  B2	=	2/3 A1 + 1/3 A2 + ¾ A3	=	½ a X - ½ 3-1/2 a Y + ¾ c Z	(Mg)	(2c)

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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