def from_bulk_and_miller(cls, structure, miller_index, min_slab_size=5.0,
min_vacuum_size=10.0, max_normal_search=None,
center_slab = True, selective_dynamics=False,
undercoord_threshold = 0.09):
"""
This method constructs the adsorbate site finder from a bulk
structure and a miller index, which allows the surface sites
to be determined from the difference in bulk and slab coordination,
as opposed to the height threshold.
Args:
structure (Structure): structure from which slab
input to the ASF is constructed
miller_index (3-tuple or list): miller index to be used
min_slab_size (float): min slab size for slab generation
min_vacuum_size (float): min vacuum size for slab generation
max_normal_search (int): max normal search for slab generation
center_slab (bool): whether to center slab in slab generation
selective dynamics (bool): whether to assign surface sites
to selective dynamics
undercoord_threshold (float): threshold of "undercoordation"
to use for the assignment of surface sites. Default is
0.1, for which surface sites will be designated if they
are 10% less coordinated than their bulk counterpart
"""
# TODO: for some reason this works poorly with primitive cells
vcf_bulk = VoronoiCoordFinder(structure)
bulk_coords = [len(vcf_bulk.get_coordinated_sites(n))
for n in range(len(structure))]
struct = structure.copy(site_properties = {'bulk_coordinations':bulk_coords})
slabs = generate_all_slabs(struct, max_index=max(miller_index),
min_slab_size=min_slab_size,
min_vacuum_size=min_vacuum_size,
max_normal_search = max_normal_search,
center_slab = center_slab)
slab_dict = {slab.miller_index:slab for slab in slabs}
if miller_index not in slab_dict:
raise ValueError("Miller index not in slab dict")
this_slab = slab_dict[miller_index]
vcf_surface = VoronoiCoordFinder(this_slab, allow_pathological=True)
surf_props = []
this_mi_vec = get_mi_vec(this_slab.miller_index)
mi_mags = [np.dot(this_mi_vec, site.coords) for site in this_slab]
average_mi_mag = np.average(mi_mags)
for n, site in enumerate(this_slab):
bulk_coord = this_slab.site_properties['bulk_coordinations'][n]
slab_coord = len(vcf_surface.get_coordinated_sites(n))
mi_mag = np.dot(this_mi_vec, site.coords)
undercoord = (bulk_coord - slab_coord)/bulk_coord
if undercoord > undercoord_threshold and mi_mag > average_mi_mag:
surf_props += ['surface']
else:
surf_props += ['subsurface']
new_site_properties = {'surface_properties':surf_props}
new_slab = this_slab.copy(site_properties=new_site_properties)
return cls(new_slab, selective_dynamics)
def _get_coord_no_sites_chrg(self, site):
"""
Compute the coordination number and coordination charge
Args:
site:
pymatgen.core.sites.Site
"""
struct = self._structure.copy()
struct.append(site.species_string, site.frac_coords)
coord_finder = VoronoiCoordFinder(struct)
coord_no = coord_finder.get_coordination_number(-1)
coord_sites = coord_finder.get_coordinated_sites(-1)
# In some cases coordination sites to interstitials include
# interstitials also.
sites_to_be_deleted = []
for i in range(len(coord_sites)):
if coord_sites[i].species_string == 'X':
sites_to_be_deleted.append(i)
sites_to_be_deleted.reverse() # So index won't change in between
for ind in sites_to_be_deleted:
del coord_sites[ind]
coord_chrg = 0
for site, weight in coord_finder.get_voronoi_polyhedra(-1).items():
if not site.species_string == 'X':
coord_chrg += weight * self._valence_dict[site.species_string]
return coord_no, coord_sites, coord_chrg
def _get_coord_no_sites_chrg(self, site):
"""
Compute the coordination number and coordination charge
Args:
site:
pymatgen.core.sites.Site
"""
struct = self._structure.copy()
struct.append(site.specie.symbol, site.frac_coords)
coord_finder = VoronoiCoordFinder(struct)
coord_no = coord_finder.get_coordination_number(-1)
coord_sites = coord_finder.get_coordinated_sites(-1)
# In some cases coordination sites to interstitials include
# interstitials also. Filtering them.
def no_inter(site):
return not site.specie.symbol == 'X'
coord_sites = filter(no_inter, coord_sites)
coord_chrg = 0
for site, weight in coord_finder.get_voronoi_polyhedra(-1).items():
if not site.specie.symbol == 'X':
coord_chrg += weight * self._valence_dict[site.species_string]
return coord_no, coord_sites, coord_chrg
def _get_coord_no_sites_chrg(self, site):
"""
Compute the coordination number and coordination charge
Args:
site:
pymatgen.core.sites.Site
"""
struct = self._structure.copy()
struct.append(site.specie.symbol, site.frac_coords)
coord_finder = VoronoiCoordFinder(struct)
coord_no = coord_finder.get_coordination_number(-1)
coord_sites = coord_finder.get_coordinated_sites(-1)
# In some cases coordination sites to interstitials include
# interstitials also. Filtering them.
def no_inter(site):
return not site.specie.symbol == 'X'
coord_sites = filter(no_inter, coord_sites)
coord_chrg = 0
for site, weight in coord_finder.get_voronoi_polyhedra(-1).items():
if not site.specie.symbol == 'X':
coord_chrg += weight * self._valence_dict[site.species_string]
return coord_no, coord_sites, coord_chrg
def _get_coord_no_sites_chrg(self, site):
"""
Compute the coordination number and coordination charge
Args:
site:
pymatgen.core.sites.Site
"""
struct = self._structure.copy()
struct.append(site.species_string, site.frac_coords)
coord_finder = VoronoiCoordFinder(struct)
coord_no = coord_finder.get_coordination_number(-1)
coord_sites = coord_finder.get_coordinated_sites(-1)
# In some cases coordination sites to interstitials include
# interstitials also.
sites_to_be_deleted = []
for i in range(len(coord_sites)):
if coord_sites[i].species_string == 'X':
sites_to_be_deleted.append(i)
sites_to_be_deleted.reverse() # So index won't change in between
for ind in sites_to_be_deleted:
del coord_sites[ind]
coord_chrg = 0
for site, weight in coord_finder.get_voronoi_polyhedra(-1).items():
if not site.species_string == 'X':
coord_chrg += weight * self._valence_dict[site.species_string]
return coord_no, coord_sites, coord_chrg
def get_voronoi(self, poscars, diff_sp):
"""
Known bug, solid_angle_tol = 0.5 works for Mn2O4 spinels. Needs to be checked for others.
solid_angle_tol is the tolerance on the solid angle, bigger the angle- closer the atoms.
"""
solid_angle_tol = 0.5
sites = []
n = int(diff_sp.values()[0][0])-1
for i in range(0, len(poscars)):
voronoi = VoronoiCoordFinder(poscars[i].structure)
sites.append(voronoi.get_coordinated_sites(n, solid_angle_tol))
return sites
class VoronoiCoordFinderTest(PymatgenTest):
def setUp(self):
s = self.get_structure('LiFePO4')
self.finder = VoronoiCoordFinder(s, [Element("O")])
def test_get_voronoi_polyhedra(self):
self.assertEqual(len(self.finder.get_voronoi_polyhedra(0).items()), 8)
def test_get_coordination_number(self):
self.assertAlmostEqual(self.finder.get_coordination_number(0),
5.809265748999465, 7)
def test_get_coordinated_sites(self):
self.assertEqual(len(self.finder.get_coordinated_sites(0)), 8)
def _coord_find(self):
"""
calls VoronoiCoordFinder to compute the coordination number,
coordination charge
"""
for i in range(self.defect_count()):
struct = self._structs[i].copy()
coord_finder = VoronoiCoordFinder(struct)
self._coord_no.append(coord_finder.get_coordination_number(-1))
self._coord_sites.append(coord_finder.get_coordinated_sites(-1))
coord_chrg = 0
for site, weight in coord_finder.get_voronoi_polyhedra(-1).items():
coord_chrg += weight * self._valence_dict[site.species_string]
self._coord_charge_no.append(coord_chrg)
def _coord_find(self):
"""
calls VoronoiCoordFinder to compute the coordination number,
coordination charge
"""
for i in range(self.defect_count()):
struct = self._structs[i].copy()
coord_finder = VoronoiCoordFinder(struct)
self._coord_no.append(coord_finder.get_coordination_number(-1))
self._coord_sites.append(coord_finder.get_coordinated_sites(-1))
coord_chrg = 0
for site, weight in coord_finder.get_voronoi_polyhedra(-1).items():
coord_chrg += weight * self._valence_dict[site.species_string]
self._coord_charge_no.append(coord_chrg)
class VoronoiCoordFinderTest(PymatgenTest):
def setUp(self):
s = self.get_structure('LiFePO4')
self.finder = VoronoiCoordFinder(s, [Element("O")])
def test_get_voronoi_polyhedra(self):
self.assertEqual(len(self.finder.get_voronoi_polyhedra(0).items()), 8)
def test_get_coordination_number(self):
self.assertAlmostEqual(self.finder.get_coordination_number(0),
5.809265748999465, 7)
def test_get_coordinated_sites(self):
self.assertEqual(len(self.finder.get_coordinated_sites(0)), 8)
def __init__(self, structure, valences, radii):
"""
Args:
structure:
pymatgen.core.structure.Structure
valences:
valences of elements as a dictionary
radii:
Radii of elements as a dictionary
"""
self._structure = structure
self._valence_dict = valences
self._rad_dict = radii
# Store symmetrically distinct sites, their coordination numbers
# coordinated_sites, effective charge
symm_finder = SymmetryFinder(self._structure)
symm_structure = symm_finder.get_symmetrized_structure()
equiv_site_seq = symm_structure.equivalent_sites
self._defect_sites = []
for equiv_sites in equiv_site_seq:
self._defect_sites.append(equiv_sites[0])
self._vac_site_indices = []
for site in self._defect_sites:
for i in range(len(self._structure.sites)):
if site == self._structure[i]:
self._vac_site_indices.append(i)
coord_finder = VoronoiCoordFinder(self._structure)
self._defectsite_coord_no = []
self._defect_coord_sites = []
for i in self._vac_site_indices:
self._defectsite_coord_no.append(
coord_finder.get_coordination_number(i)
)
self._defect_coord_sites.append(
coord_finder.get_coordinated_sites(i)
)
# Store the ionic radii for the elements in the structure
# (Used to computing the surface are and volume)
# Computed based on valence of each element
self._vac_eff_charges = None
self._vol = None
self._sa = None
def __init__(self, structure, valences, radii):
"""
Args:
structure:
pymatgen.core.structure.Structure
valences:
valences of elements as a dictionary
radii:
Radii of elements as a dictionary
"""
self._structure = structure
self._valence_dict = valences
self._rad_dict = radii
# Store symmetrically distinct sites, their coordination numbers
# coordinated_sites, effective charge
symm_finder = SymmetryFinder(self._structure)
symm_structure = symm_finder.get_symmetrized_structure()
equiv_site_seq = symm_structure.equivalent_sites
self._defect_sites = []
for equiv_sites in equiv_site_seq:
self._defect_sites.append(equiv_sites[0])
self._vac_site_indices = []
for site in self._defect_sites:
for i in range(len(self._structure.sites)):
if site == self._structure[i]:
self._vac_site_indices.append(i)
coord_finder = VoronoiCoordFinder(self._structure)
self._defectsite_coord_no = []
self._defect_coord_sites = []
for i in self._vac_site_indices:
self._defectsite_coord_no.append(
coord_finder.get_coordination_number(i))
self._defect_coord_sites.append(
coord_finder.get_coordinated_sites(i))
# Store the ionic radii for the elements in the structure
# (Used to computing the surface are and volume)
# Computed based on valence of each element
self._vac_eff_charges = None
self._vol = None
self._sa = None
class VoronoiCoordFinderTest(unittest.TestCase):
def setUp(self):
filepath = os.path.join(test_dir, 'vasprun.xml')
reader = Vasprun(filepath)
s = reader.final_structure
self.finder = VoronoiCoordFinder(s,[Element("O")])
def test_get_voronoi_polyhedra(self):
self.assertEqual(len(self.finder.get_voronoi_polyhedra(0).items()),10, "Incorrect number of results returned for get_voronoi_polyhedra")
def test_get_coordination_number(self):
print self.finder.get_coordination_number(0)
self.assertAlmostEqual(self.finder.get_coordination_number(0), 5.60588600732, 7, "Incorrect coordination number returned!")
def test_get_coordinated_sites(self):
self.assertEqual(len(self.finder.get_coordinated_sites(0)), 10)
class VoronoiCoordFinderTest(unittest.TestCase):
def setUp(self):
filepath = os.path.join(test_dir, 'LiFePO4.cif')
parser = CifParser(filepath)
s = parser.get_structures()[0]
self.finder = VoronoiCoordFinder(s, [Element("O")])
def test_get_voronoi_polyhedra(self):
self.assertEqual(len(self.finder.get_voronoi_polyhedra(0).items()), 8,
"Incorrect number of results returned for " +
"get_voronoi_polyhedra")
def test_get_coordination_number(self):
self.assertAlmostEqual(self.finder.get_coordination_number(0),
5.809265748999465, 7)
def test_get_coordinated_sites(self):
self.assertEqual(len(self.finder.get_coordinated_sites(0)), 8)
class VoronoiCoordFinderTest(unittest.TestCase):
def setUp(self):
filepath = os.path.join(test_dir, 'LiFePO4.cif')
parser = CifParser(filepath)
s = parser.get_structures()[0]
self.finder = VoronoiCoordFinder(s, [Element("O")])
def test_get_voronoi_polyhedra(self):
self.assertEqual(
len(self.finder.get_voronoi_polyhedra(0).items()), 8,
"Incorrect number of results returned for " +
"get_voronoi_polyhedra")
def test_get_coordination_number(self):
self.assertAlmostEqual(self.finder.get_coordination_number(0),
5.809265748999465, 7)
def test_get_coordinated_sites(self):
self.assertEqual(len(self.finder.get_coordinated_sites(0)), 8)
print('space group symbol of structure1:',
spacegroup1.get_space_group_symbol())
print('space group number of structure1:',
spacegroup1.get_space_group_number())
print('space group symbol of structure2:',
spacegroup2.get_space_group_symbol())
print('space group number of structure2:',
spacegroup2.get_space_group_number())
Voronoi = VoronoiCoordFinder(s2, target=None)
site = s2.num_sites
#print("s2[0]:",s2.sites)
print("s2_cart_coords[0]", s2.cart_coords[0])
#print("s2_distance_(0,1)",s2.get_distance(0,1))
polyhedra = Voronoi.get_voronoi_polyhedra(1)
coordinate = Voronoi.get_coordination_number(1)
coordinate_sites = Voronoi.get_coordinated_sites(1)
Voronoi_Analyzer = VoronoiAnalyzer()
anay = Voronoi_Analyzer.analyze(s1, n=0)
strucs = [s1, s2]
anays = Voronoi_Analyzer.analyze_structures(strucs)
print("Voronoi_Analyzer.analyze(s1,n=0):", anay)
#plt = Voronoi_Analyzer.plot_vor_analysis(anays)
relax = RelaxationAnalyzer(s1, s2)
volume_change = relax.get_percentage_volume_change()
lattice_parameter_changes = relax.get_percentage_lattice_parameter_changes()
print('initial volume:', s1.volume)
print('final volume:', s2.volume)
print("percent_volume_change:", volume_change)
print("percent_lattice_change:", lattice_parameter_changes)
bond_dist = relax.get_percentage_bond_dist_changes(max_radius=6)
print("percent_bond_distance_change:", bond_dist)
def from_bulk_and_miller(cls,
structure,
miller_index,
min_slab_size=8.0,
min_vacuum_size=10.0,
max_normal_search=None,
center_slab=True,
selective_dynamics=False,
undercoord_threshold=0.09):
"""
This method constructs the adsorbate site finder from a bulk
structure and a miller index, which allows the surface sites
to be determined from the difference in bulk and slab coordination,
as opposed to the height threshold.
Args:
structure (Structure): structure from which slab
input to the ASF is constructed
miller_index (3-tuple or list): miller index to be used
min_slab_size (float): min slab size for slab generation
min_vacuum_size (float): min vacuum size for slab generation
max_normal_search (int): max normal search for slab generation
center_slab (bool): whether to center slab in slab generation
selective dynamics (bool): whether to assign surface sites
to selective dynamics
undercoord_threshold (float): threshold of "undercoordation"
to use for the assignment of surface sites. Default is
0.1, for which surface sites will be designated if they
are 10% less coordinated than their bulk counterpart
"""
# TODO: for some reason this works poorly with primitive cells
# may want to switch the coordination algorithm eventually
vcf_bulk = VoronoiCoordFinder(structure)
bulk_coords = [
len(vcf_bulk.get_coordinated_sites(n, tol=0.05))
for n in range(len(structure))
]
struct = structure.copy(
site_properties={'bulk_coordinations': bulk_coords})
slabs = generate_all_slabs(struct,
max_index=max(miller_index),
min_slab_size=min_slab_size,
min_vacuum_size=min_vacuum_size,
max_normal_search=max_normal_search,
center_slab=center_slab)
slab_dict = {slab.miller_index: slab for slab in slabs}
if miller_index not in slab_dict:
raise ValueError("Miller index not in slab dict")
this_slab = slab_dict[miller_index]
vcf_surface = VoronoiCoordFinder(this_slab, allow_pathological=True)
surf_props, undercoords = [], []
this_mi_vec = get_mi_vec(this_slab)
mi_mags = [np.dot(this_mi_vec, site.coords) for site in this_slab]
average_mi_mag = np.average(mi_mags)
for n, site in enumerate(this_slab):
bulk_coord = this_slab.site_properties['bulk_coordinations'][n]
slab_coord = len(vcf_surface.get_coordinated_sites(n, tol=0.05))
mi_mag = np.dot(this_mi_vec, site.coords)
undercoord = (bulk_coord - slab_coord) / bulk_coord
undercoords += [undercoord]
if undercoord > undercoord_threshold and mi_mag > average_mi_mag:
surf_props += ['surface']
else:
surf_props += ['subsurface']
new_site_properties = {
'surface_properties': surf_props,
'undercoords': undercoords
}
new_slab = this_slab.copy(site_properties=new_site_properties)
return cls(new_slab, selective_dynamics)
