Crystal Lattice Structures:	Creation Date: 15 Apr 2001
	Last Modified: 21 Oct 2004

The CO (B21) 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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• The CO molecules sit on the sites of an fcc lattice, however each of the four molecules in the unit cell is oriented differently. Note that this structure has the identical symmetry and Wyckoff positions as the FeSi (B20) structure, except that the atoms are closer together.

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• Prototype: CO
• Pearson Symbol: cP8
• Strukturbericht Designation: B21
• Space Group: P2₁3 (Cartesian and lattice coordinate listings available)
• Number: 198
• Primitive Vectors:

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

• Basis Vectors:

  B1	=	x1 aX	+ x1 aY	+ x1 aZ	(4a)	(C)
  B2	=	(½ + x1) aX	+ (½ - x1) aY	- x1 aZ	(4a)	(C)
  B3	=	- x1 aX	+ (½ + x1) aY	+ (½ - x1) aZ	(4a)	(C)
  B4	=	(½ - x1) aX	- x1 aY	+ (½ + x1) aZ	(4a)	(C)
  B5	=	x2 aX	+ x2 aY	+ x2 aZ	(4a)	(O)
  B6	=	(½ + x2) aX	+ (½ - x2) aY	- x2 aZ	(4a)	(O)
  B7	=	- x2 aX	+ (½ + x2) aY	+ (½ - x2) aZ	(4a)	(O)
  B8	=	(½ - x2) aX	- x2 aY	+ (½ + x2) aZ	(4a)	(O)

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Go back to the IIIb-VIIb Structures page.

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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).