Plane Create


A crystallographic plane does not exist as a single plane, is always part of a family of infinite planes, passing through all the lattice nodes, with equal distances between them. Each plane of a family (h k l) intersects the lattice in n/h n/k n/l, where n = 0 means the plane passing through the origin and n = 1 is the usual representation of the plane closest to the origin. The order parameter indicates the value of n for a specific plane.

o1, o2, o3

A plane can also be defined indicating explicitly the coordinates of a node where the plane passes. For each plane family, there is a plane passing through the origin node and as nodes are equivalent, it follows that for any node, there is a plane of any family passing through there.

When the lattice is primitive or vectors are primitive, coordinates o1, o2, o3 are enough to identify any cell node. No default node exists as the default plane order (1) cannot be associated to a specific node for all lattices.

Example: <cell ... o1="1" o2="0" o3="0"/> (no default)
Allowed values: integer (optional, coupled)


When the lattice is centered and vectors are conventional, the coordinates o1, o2, o3 indicate the node in the lower-left corner of the cell where the plane passes. a fourth coordinate o4 is needed to point the centered node where the plane passes. By default, o4 is 000, so no change is introduced. When the cell lattice is primitive P or the vectors defining the node are primitive, that is the only possible value for o4. For I, C, F, R centered lattices, o4 can also take the values:
I: 111
C: 110
F: 110, 101, 011
R: 211, 122

Example: <plane ... o4="000"/> (default)
Allowed values: 000, 111, 110 101, 011, 211, 122 (optional)


The geometric data defining a polygon plane must be entered in order to make the plane completely independent from its reference objects. This is accomplished with two data child elements, one containig real data (the xyz coordinates), the other containing integer data (the number of loops, 1, the number of vertices for the loop, n, the offset of the vertices for the loop, from 0 to n-1).
<data ... name="points" type="double" size="9">
-1.0000 0.0000 0.0000 1.0000 0.0000 0.0000 0.0000 1.0000 0.0000
</data> Allowed values: real (required)

<data ... name="points_driver" type="int" size="5">
1 3 0 1 2 </data> Allowed values: integer (required)