Update structuredata.md

docs/source/user_guide/structuredata/structuredata.md

@@ -115,7 +115,7 @@ Units of magnetization are Bohr magnetons.
 TOBE ADDED: See the corresponding page on `magnetization` to have a full description of the property.
 
 **Property definition**: in the constructor, each property is provided by means of standard python built-in data types, e.g. lists, tuples, int and so on. We allow only a unique way to define/provide a given property, e.g. magnetization must be always provided as a *list of 3D vectors*, one for each atom (even if the magnetization is zero somewhere). This will simplify types, units and consistency checks.
-Some property class will be provided with classmethods used to convert from other to the pre-defined format. For example, we can invoke `Magnetization.from_collinear([1,-1,...0],direction=[cos(a),cos(b),cos(c)])` to produce the required list of 3D vectors needed in our StructureData instance definition. We may also define a `to_collinear` methods, but this will not be useful in terms of the property definition inside the StructureData node. 
+Some property class will be provided with classmethods used to convert from other to the pre-defined format. For example, we can invoke `Magnetization.from_collinear([1,-1,...0],direction=[cos(a),cos(b),cos(c)])` to produce the required list of 3D vectors needed in our StructureData instance definition. We may also define a `to_collinear` methods, but this will not be useful in terms of the property definition inside the StructureData node: it can be useful in case we need to provide some different format in particular plugins. 
 
 ## The immutability of the `StructureData` instance and constructors