type
Controls the representation of the cell lattice, which can be:
1)
conventional (the lattice is constructed using
n1,
n2,
n3 conventional cells; 2)
primitive (the lattice
is constructed using
n1,
n2,
n3 primitive cells);
3)
wigner (the lattice is constructed using
n1,
n2,
n3 Wigner-Seitz cells); 4)
parallelepiped (the lattice is filtered
by a generic parallelepiped volume, with length parameters
v1,
v2,
v3 and angle parameters
v12,
v13,
v23);
5)
sphere (the lattice is filtered by a sphere with radius
v1);
6)
projection (the lattice is represented by its stereographic projection).
Example: <cell ... type="conventional"/> (default)
Allowed values: conventional, primitive
wigner, parallelepiped, sphere,
projection (optional)
n1, n2, n3
Control the number of lattice cells created along
the directions defined by the vectors
a,
b,
c,
when
type is
conventional,
primitive
or
wigner. Indicating some or all of these parameters when
the cell type does not require them is flagged as an error.
Example: <cell ... n1="1" n2="2" n3="3"/> (default)
Allowed values: positive integer (optional, coupled)
v1, v2, v3, v12, v13, v23
When
type is
parallelepiped, these six parameters are needed
to indicate the edge lengths and angles of the filtering parallelepiped.
Each angle must be smaller than the sum of the other two and must be larger
than the absolute difference of the other two, otherwise an error is produced.
When
type is
sphere, the
v1 parameter is needed to
indicate the radius of the filtering sphere. Setting parameters that are
not required for a given cell type is flagged as an error.
Example: <cell ... v1="5.0" v2="6.0" v3="7.0"
v12="60.0" v13="70.0" v23="80.0"/> (no default)
Allowed values: positive real (required)