Crystal Lattice Structures:	Creation Date: 12 Sep 2002
	Last Modified: 21 Oct 2004

The Hypothetical cI54 Ferrite 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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• Ferrite is steel with a bcc structure. This structure represents one possible ordering which might be found in an Fe-Ni-Cr steel. Note that it is not meant to represent a real steel.
• If we replace the Cr and Ni atoms by Fe, and take x₁ = 1/6, x₂ = y₃ = 1/3, this becomes the bcc (A2) structure with a_bcc = a/3.
• This is the same structure as Sb₂Tl₇. It's just that we thought of this before we thought to look in Pearson's Handbook.

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• Prototype: CrFe₂₀Ni₆ (hypothetical)
• Pearson Symbol: cI54
• Space Group: Im3m (Cartesian and lattice coordinate listings available)
• Number: 229
• Primitive Vectors:

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

• Basis Vectors:

  B1	=		0		(Cr)	(2a)
  B2	=	+ 2 x1 A1 + 2 x1 A2 + 2 x1 A3	=	+ x1 a X + x1 a Y + x1 a Z	(Fe-I)	(16f)
  B3	=	+ 2 x1 A1	=	- x1 a X + x1 a Y + x1 a Z	(Fe-I)	(16f)
  B4	=	+ 2 x1 A2	=	+ x1 a X - x1 a Y + x1 a Z	(Fe-I)	(16f)
  B5	=	+ 2 x1 A3	=	+ x1 a X + x1 a Y - x1 a Z	(Fe-I)	(16f)
  B6	=	- 2 x1 A1 - 2 x1 A2 - 2 x1 A3	=	- x1 a X - x1 a Y - x1 a Z	(Fe-I)	(16f)
  B7	=	- 2 x1 A1	=	+ x1 a X - x1 a Y - x1 a Z	(Fe-I)	(16f)
  B8	=	- 2 x1 A2	=	- x1 a X + x1 a Y - x1 a Z	(Fe-I)	(16f)
  B9	=	- 2 x1 A3	=	- x1 a X - x1 a Y + x1 a Z	(Fe-I)	(16f)
  B10	=	+ x2 A2 + x2 A3	=	+ x2 a X	(Ni)	(12e)
  B11	=	+ x2 A1 + x2 A3	=	+ x2 a Y	(Ni)	(12e)
  B12	=	+ x2 A1 + x2 A2	=	+ x2 a Z	(Ni)	(12e)
  B13	=	- x2 A2 - x2 A3	=	- x2 a X	(Ni)	(12e)
  B14	=	- x2 A1 - x2 A3	=	- x2 a Y	(Ni)	(12e)
  B15	=	- x2 A1 - x2 A2	=	- x2 a Z	(Ni)	(12e)
  B16	=	+ 2 y3 A1 + y3 A2 + y3 A3	=	+ y3 a Y + y3 a Z	(Fe-II)	(24h)
  B17	=	+ y3 A1 + 2 y3 A2 + y3 A3	=	+ y3 a X + y3 a Z	(Fe-II)	(24h)
  B18	=	+ y3 A1 + y3 A2 + 2 y3 A3	=	+ y3 a X + y3 a Y	(Fe-II)	(24h)
  B19	=	- y3 A2 + y3 A3	=	+ y3 a Y - y3 a Z	(Fe-II)	(24h)
  B20	=	- y3 A1 + y3 A3	=	+ y3 a X - y3 a Z	(Fe-II)	(24h)
  B21	=	- y3 A1 + y3 A2	=	+ y3 a X - y3 a Y	(Fe-II)	(24h)
  B22	=	- 2 y3 A1 - y3 A2 - y3 A3	=	- y3 a Y - y3 a Z	(Fe-II)	(24h)
  B23	=	- y3 A1 - 2 y3 A2 - y3 A3	=	- y3 a X - y3 a Z	(Fe-II)	(24h)
  B24	=	- y3 A1 - y3 A2 - 2 y3 A3	=	- y3 a X - y3 a Y	(Fe-II)	(24h)
  B25	=	+ y3 A2 - y3 A3	=	- y3 a Y + y3 a Z	(Fe-II)	(24h)
  B26	=	+ y3 A1 - y3 A3	=	- y3 a X + y3 a Z	(Fe-II)	(24h)
  B27	=	+ y3 A1 - y3 A2	=	- y3 a X + y3 a Y	(Fe-II)	(24h)

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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).