</P>

<PRE>lattice style scale keyword values ... 

</PRE>

<UL><LI>style = <I>none</I> or <I>sc</I> or <I>bcc</I> or <I>fcc</I> or <I>diamond</I> or         <I>sq</I> or <I>sq2</I> or <I>hex</I> or <I>custom</I> 

<UL><LI>style = <I>none</I> or <I>sc</I> or <I>bcc</I> or <I>fcc</I> or <I>hcp</I> or <I>diamond</I> or         <I>sq</I> or <I>sq2</I> or <I>hex</I> or <I>custom</I> 

<LI>scale = scale factor between lattice and simulation box 

</P>

<P>The lattice style must be consistent with the dimension of the

simulation - see the <A HREF = "dimension.html">dimension</A> command.  Styles <I>sc</I>

or <I>bcc</I> or <I>fcc</I> or <I>diamond</I> are for 3d problems.  Styles <I>sq</I> or

<I>sq2</I> or <I>hex</I> are for 2d problems.  Style <I>custom</I> can be used for

either 2d or 3d problems.

or <I>bcc</I> or <I>fcc</I> or <I>hcp</I> or <I>diamond</I> are for 3d problems.  Styles

<I>sq</I> or <I>sq2</I> or <I>hex</I> are for 2d problems.  Style <I>custom</I> can be

used for either 2d or 3d problems.

</P>

<P>A lattice consists of a unit cell, a set of basis atoms within that

cell, and a set of transformation parameters (scale, origin, orient)

<P>Lattices of style <I>sc</I>, <I>fcc</I>, <I>bcc</I>, and <I>diamond</I> are 3d lattices

that define a cubic unit cell with edge length = 1.0.  This means a1 =

1.0 0.0 0.0, a2 = 0.0 1.0 0.0, and a3 = 0.0 0.0 1.0.  The placement of

the basis atoms within the unit cell are described in any solid-state

physics text.  A <I>sc</I> lattice has 1 basis atom at the

lower-left-bottom corner of the cube.  A <I>bcc</I> lattice has 2 basis

atoms, one at the corner and one at the center of the cube.  A <I>fcc</I>

lattice has 4 basis atoms, one at the corner and 3 at the cube face

centers.  A <I>diamond</I> lattice has 8 basis atoms.

1 0 0, a2 = 0 1 0, and a3 = 0 0 1.  Style <I>hcp</I> has a1 = 1 0 0, a2 = 0

sqrt(3) 0, and a3 = 0 0 sqrt(8/3).  The placement of the basis atoms

within the unit cell are described in any solid-state physics text.  A

<I>sc</I> lattice has 1 basis atom at the lower-left-bottom corner of the

cube.  A <I>bcc</I> lattice has 2 basis atoms, one at the corner and one at

the center of the cube.  A <I>fcc</I> lattice has 4 basis atoms, one at the

corner and 3 at the cube face centers.  A <I>hcp</I> lattice has 4 basis

atoms, two in the z = 0 plane and 2 in the z = 0.5 plane.  A <I>diamond</I>

lattice has 8 basis atoms.

</P>

<P>Lattices of style <I>sq</I> and <I>sq2</I> are 2d lattices that define a square

unit cell with edge length = 1.0.  This means a1 = 1.0 0.0 0.0 and a2

= 0.0 1.0 0.0.  A <I>sq</I> lattice has 1 basis atom at the lower-left

corner of the square.  A <I>sq2</I> lattice has 2 basis atoms, one at the

corner and one at the center of the square.  A <I>hex</I> style is also a

2d lattice, but the unit cell is rectangular, with a1 = 1.0 0.0 0.0

and a2 = 0.0 sqrt(3.0) 0.0.  It has 2 basis atoms, one at the corner

and one at the center of the rectangle.

unit cell with edge length = 1.0.  This means a1 = 1 0 0 and a2 = 0 1

0.  A <I>sq</I> lattice has 1 basis atom at the lower-left corner of the

square.  A <I>sq2</I> lattice has 2 basis atoms, one at the corner and one

at the center of the square.  A <I>hex</I> style is also a 2d lattice, but

the unit cell is rectangular, with a1 = 1 0 0 and a2 = 0 sqrt(3) 0.

It has 2 basis atoms, one at the corner and one at the center of the

rectangle.

</P>

<P>A lattice of style <I>custom</I> allows you to specify a1, a2, a3, and a

list of basis atoms to put in the unit cell.  By default, a1,a2,a3 are

lattice style scale keyword values ... :pre

style = {none} or {sc} or {bcc} or {fcc} or {diamond} or \

style = {none} or {sc} or {bcc} or {fcc} or {hcp} or {diamond} or \

        {sq} or {sq2} or {hex} or {custom} :ulb,l

scale = scale factor between lattice and simulation box :l

  for style {none}:

The lattice style must be consistent with the dimension of the

simulation - see the "dimension"_dimension.html command.  Styles {sc}

or {bcc} or {fcc} or {diamond} are for 3d problems.  Styles {sq} or

{sq2} or {hex} are for 2d problems.  Style {custom} can be used for

either 2d or 3d problems.

or {bcc} or {fcc} or {hcp} or {diamond} are for 3d problems.  Styles

{sq} or {sq2} or {hex} are for 2d problems.  Style {custom} can be

used for either 2d or 3d problems.

A lattice consists of a unit cell, a set of basis atoms within that

cell, and a set of transformation parameters (scale, origin, orient)

Lattices of style {sc}, {fcc}, {bcc}, and {diamond} are 3d lattices

that define a cubic unit cell with edge length = 1.0.  This means a1 =

1.0 0.0 0.0, a2 = 0.0 1.0 0.0, and a3 = 0.0 0.0 1.0.  The placement of

the basis atoms within the unit cell are described in any solid-state

physics text.  A {sc} lattice has 1 basis atom at the

lower-left-bottom corner of the cube.  A {bcc} lattice has 2 basis

atoms, one at the corner and one at the center of the cube.  A {fcc}

lattice has 4 basis atoms, one at the corner and 3 at the cube face

centers.  A {diamond} lattice has 8 basis atoms.

1 0 0, a2 = 0 1 0, and a3 = 0 0 1.  Style {hcp} has a1 = 1 0 0, a2 = 0

sqrt(3) 0, and a3 = 0 0 sqrt(8/3).  The placement of the basis atoms

within the unit cell are described in any solid-state physics text.  A

{sc} lattice has 1 basis atom at the lower-left-bottom corner of the

cube.  A {bcc} lattice has 2 basis atoms, one at the corner and one at

the center of the cube.  A {fcc} lattice has 4 basis atoms, one at the

corner and 3 at the cube face centers.  A {hcp} lattice has 4 basis

atoms, two in the z = 0 plane and 2 in the z = 0.5 plane.  A {diamond}

lattice has 8 basis atoms.

Lattices of style {sq} and {sq2} are 2d lattices that define a square

unit cell with edge length = 1.0.  This means a1 = 1.0 0.0 0.0 and a2

= 0.0 1.0 0.0.  A {sq} lattice has 1 basis atom at the lower-left

corner of the square.  A {sq2} lattice has 2 basis atoms, one at the

corner and one at the center of the square.  A {hex} style is also a

2d lattice, but the unit cell is rectangular, with a1 = 1.0 0.0 0.0

and a2 = 0.0 sqrt(3.0) 0.0.  It has 2 basis atoms, one at the corner

and one at the center of the rectangle.

unit cell with edge length = 1.0.  This means a1 = 1 0 0 and a2 = 0 1

0.  A {sq} lattice has 1 basis atom at the lower-left corner of the

square.  A {sq2} lattice has 2 basis atoms, one at the corner and one

at the center of the square.  A {hex} style is also a 2d lattice, but

the unit cell is rectangular, with a1 = 1 0 0 and a2 = 0 sqrt(3) 0.

It has 2 basis atoms, one at the corner and one at the center of the

rectangle.

A lattice of style {custom} allows you to specify a1, a2, a3, and a

list of basis atoms to put in the unit cell.  By default, a1,a2,a3 are