This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
The Fourier coefficients (Φhkl) of an electrostatic potential φ(x, y, z) in a crystal can be given by,
Ω -- The volume of the unit cell (= a · (b × c)),
a, b, c -- The basis vectors of the unit cell,
h, k, l -- The Miller indices of the reflecting net
x, y, z -- The fractional coordinates of atoms in
the unit cell.
Note that the dimension of the Fourier coefficients (Φhkl) is volts times cube of length. The physics meaning of these mathematical Fourier coefficients is the electron waves that are scattered by the electrostatic potential of the crystal in the directions determined by Bragg’s law.