def electronic_coupling_direction(initial, final, couplings=None):
"""
Allows transfer along a single direction
:param initial: initial states list
:param final: final states list
:param couplings: coupling list
:return: rate constant
"""
r_vector = initial[1].get_center().get_coordinates(
) - initial[0].get_center().get_coordinates()
cell_incr = initial[0].cell_state - final[0].cell_state
r = distance_vector_periodic(r_vector, initial[0].supercell, cell_incr)
norm = np.linalg.norm(r)
dot_a = np.abs(np.dot(r, [1, 0])) / np.linalg.norm([1, 0]) / norm
dot_ab_1 = np.abs(np.dot(r, [1, 1])) / np.linalg.norm([1, 1]) / norm
dot_ab_2 = np.abs(np.dot(r, [1, -1])) / np.linalg.norm([1, -1]) / norm
dot_b = np.abs(np.dot(r, [0, 1])) / np.linalg.norm([0, 1]) / norm
#print('->', dot_a, dot_ab_1, dot_ab_1, dot_b)
ichosen = int(np.argmax([dot_a, dot_ab_1, dot_ab_2, dot_b]))
# print('coup: ', ['a', 'ab', 'ab', 'b'][ichosen])
return couplings[ichosen] # eV
def get_neighbours_num(self, center):
radius = self.cutoff_radius
center_position = self.molecules[center].get_coordinates()
def get_supercell_increments(supercell, radius):
# TODO: This function can be optimized as a function of the particular molecule coordinates
v = np.array(radius/np.linalg.norm(supercell, axis=1), dtype=int) + 1 # here extensive approximation
return list(itertools.product(*[range(-i, i+1) for i in v]))
cell_increments = get_supercell_increments(self.supercell, radius)
if not '{}_{}'.format(center, radius) in self.neighbors:
neighbours = []
jumps = []
for i, molecule in enumerate(self.molecules):
coordinates = molecule.get_coordinates()
for cell_increment in cell_increments:
r_vec = distance_vector_periodic(coordinates - center_position, self.supercell, cell_increment)
if 0 < np.linalg.norm(r_vec) < radius:
neighbours.append(i)
jumps.append(cell_increment)
neighbours = np.array(neighbours)
jumps = np.array(jumps)
self.neighbors['{}_{}'.format(center, radius)] = [neighbours, jumps]
return self.neighbors['{}_{}'.format(center, radius)]
def get_state_neighbors(self, ref_state):
if ref_state not in self._state_neighbors:
radius = self.cutoff_radius
center_position = ref_state.get_coordinates_relative(self.supercell)
def get_supercell_increments(supercell, radius):
# TODO: This function can be optimized as a function of the particular molecule coordinates
v = np.array(radius/np.linalg.norm(supercell, axis=1), dtype=int) + 1 # here extensive approximation
return list(itertools.product(*[range(-i, i+1) for i in v]))
cell_increments = get_supercell_increments(self.supercell, radius)
# Get neighbor non ground states
state_neighbors = []
state_cell_incr = []
# for state in self.get_ground_states() + self.get_states():
for state in self.get_states():
coordinates = state.get_coordinates()
for cell_increment in cell_increments:
r_vec = distance_vector_periodic(coordinates - center_position, self.supercell, cell_increment)
if 0 < np.linalg.norm(r_vec) < radius:
state_neighbors.append(state)
state_cell_incr.append(list(cell_increment))
# Include neighbor ground states
state_neighbors_gs, state_cell_incr_gs = self.get_ground_states_improved(ref_state)
state_cell_incr = state_cell_incr_gs + state_cell_incr
state_neighbors = state_neighbors_gs + state_neighbors
self._state_neighbors[ref_state] = [state_neighbors, state_cell_incr]
return self._state_neighbors[ref_state]
def get_state_neighbors_copy(self, ref_state):
"""
Not used for now. To be deprecated in the future
:param ref_state:
:return:
"""
radius = self.cutoff_radius
center_position = ref_state.get_coordinates_relative(self.supercell)
def get_supercell_increments(supercell, radius):
# TODO: This function can be optimized as a function of the particular molecule coordinates
v = np.array(radius/np.linalg.norm(supercell, axis=1), dtype=int) + 1 # here extensive approximation
return list(itertools.product(*[range(-i, i+1) for i in v]))
cell_increments = get_supercell_increments(self.supercell, radius)
neighbours = []
for state in self.get_ground_states():
coordinates = state.get_coordinates()
for cell_increment in cell_increments:
r_vec = distance_vector_periodic(coordinates - center_position, self.supercell, cell_increment)
if 0 < np.linalg.norm(r_vec) < radius:
state = state.copy()
state.cell_state = ref_state.cell_state + cell_increment
neighbours.append(state)
return neighbours
def intermolecular_vector(molecule_1, molecule_2, supercell, cell_incr):
"""
:param molecule_1: donor
:param molecule_2: acceptor
:return: the distance between the donor and the acceptor
"""
position_d = molecule_1.get_coordinates()
position_a = molecule_2.get_coordinates()
r_vector = position_a - position_d
r = distance_vector_periodic(r_vector, supercell, cell_incr)
return r
def distance_matrix(molecules_list, supercell, max_distance=1):
# Set maximum possible distance everywhere
distances = np.ones(
(len(molecules_list), len(molecules_list))) * np.product(
np.diag(supercell))
for i, mol_i in enumerate(molecules_list):
for j, mol_j in enumerate(molecules_list):
coordinates = mol_i.get_coordinates()
center_position = mol_j.get_coordinates()
cell_increments = get_supercell_increments(supercell, max_distance)
for cell_increment in cell_increments:
r_vec = distance_vector_periodic(coordinates - center_position,
supercell, cell_increment)
d = np.linalg.norm(r_vec)
if distances[i, j] > d:
distances[i, j] = d
return distances
