Dielectric function tools
ComplexSignal and can
thus access complex properties. To convert a
ComplexSignal to a
make sure that the signal dimension and signal type are properly set:
Number of effective electrons
The Bethe f-sum rule gives rise to two definitions of the effective number (see [Egerton2011]):
where \(n_a\) is the number of atoms (or molecules) per unit volume of the sample, \(\epsilon_0\) is the vacuum permittivity, \(m_0\) is the electron mass and \(e\) is the electron charge.
method computes both.
Compute the electron energy-loss signal
“naively” computes the single-scattering electron-energy loss spectrum from the
dielectric function given the zero-loss peak (or its integral) and the sample
where \(I_0\) is the zero-loss peak integral, \(t\) the sample thickness, \(\beta\) the collection semi-angle and \(\theta(E)\) the characteristic scattering angle.