def calc_fb(self, h, k, l):
'''Calculate the structure factors from the bulk
'''
dinv = self.unit_cell.abs_hkl(h, k, l)
x, y, z, el, u, oc, c = self.bulk._extract_values()
oc = oc/float(len(self.bulk_sym))
f = sxrd._get_f(self.inst, el, dinv)
# Calculate the "shape factor" for the CTRs
eff_thick = self.unit_cell.c/np.sin(self.inst.alpha*np.pi/180.0)
alpha = (2.82e-5*self.inst.wavel*eff_thick/self.unit_cell.vol()*
np.sum(f.imag,1))
denom = np.exp(2.0*np.pi*1.0J*l)*np.exp(-alpha) - 1.0
# Delta functions to remove finite size effect in hk plane
delta_funcs=(abs(h - np.round(h)) < 1e-12)*(
abs(k - np.round(k)) < 1e-12)
# Sum up the uc struct factors
f_u = np.sum(oc*f*np.exp(-2*np.pi**2*u*dinv[:, np.newaxis]**2)*
np.sum([np.exp(2.0*np.pi*1.0J*(
h[:,np.newaxis]*sym_op.trans_x(x, y) +
k[:,np.newaxis]*sym_op.trans_y(x, y) +
l[:,np.newaxis]*z [np.newaxis, :]))
for sym_op in self.bulk_sym], 0)
,1)
# Putting it all togheter
fb = f_u/denom*delta_funcs
return fb
def calc_fslab(self, slablist, sym, h, k, l):
'''Calculate the structure factors from the bulk
'''
dinv = self.unit_cell.abs_hkl(h, k, l)
x, y, z, u, oc, el, t_lay = self._extract_slab_values(slablist,
sym)
oc = oc/float(len(sym))
f = sxrd._get_f(self.inst, el, dinv)
# Sum up the uc struct factors
f_u = np.sum(oc*f*np.exp(-2*np.pi**2*u*dinv[:, np.newaxis]**2)*
np.sum([np.exp(2.0*np.pi*1.0J*(
h[:,np.newaxis]*sym_op.trans_x(x, y) +
k[:,np.newaxis]*sym_op.trans_y(x, y) +
l[:,np.newaxis]*z [np.newaxis, :]))
for sym_op in sym], 0)
,1)
#return f_u, (z.max() - z.min())*np.ones(l.shape)
return f_u, t_lay*np.ones(l.shape)
