def test_get_symmetrically_equivalent_miller_indices(self):
# Tests to see if the function obtains all equivalent hkl for cubic (100)
indices001 = [(1, 0, 0), (0, 1, 0), (0, 0, 1), (0, 0, -1), (0, -1, 0), (-1, 0, 0)]
indices = get_symmetrically_equivalent_miller_indices(self.cscl, (1,0,0))
self.assertTrue(all([hkl in indices for hkl in indices001]))
# Tests to see if it captures expanded Miller indices in the family e.g. (001) == (002)
hcp_indices_100 = get_symmetrically_equivalent_miller_indices(self.Mg, (1,0,0))
hcp_indices_200 = get_symmetrically_equivalent_miller_indices(self.Mg, (2,0,0))
self.assertEqual(len(hcp_indices_100)*2, len(hcp_indices_200))
self.assertEqual(len(hcp_indices_100), 6)
def get_surface_data(self, material_id, miller_index=None):
"""
Gets surface data for a material. Useful for Wulff shapes.
Reference for surface data:
Tran, R., Xu, Z., Radhakrishnan, B., Winston, D., Sun, W., Persson, K.
A., & Ong, S. P. (2016). Data Descripter: Surface energies of elemental
crystals. Scientific Data, 3(160080), 1–13.
http://dx.doi.org/10.1038/sdata.2016.80
Args:
material_id (str): Materials Project material_id, e.g. 'mp-123'.
miller_index (list of integer): The miller index of the surface.
e.g., [3, 2, 1]. If miller_index is provided, only one dictionary
of this specific plane will be returned.
Returns:
Surface data for material. Energies are given in SI units (J/m^2).
"""
doc = self.surface_properties.get_document_by_id(material_id)
structure = self.get_structure_by_material_id(material_id)
if miller_index:
eq_indices = get_symmetrically_equivalent_miller_indices(
structure, miller_index
)
for surface in doc.surfaces:
if tuple(surface.miller_index) in eq_indices:
return surface.dict()
else:
return doc.dict()
