A computationally simple method of calculating nonspherical charge distributions in solids from linear-muffin-tin-orbital band-structure calculations is described. The charge distribution is described accurately in the region between muffin-tin spheres in terms of wave functions based on 'pseudo-muffin-tin' orbitals. The nonsphericity inside the spheres as described by the same orbitals is less accurate. For several applications, however, this is not serious. The density can easily be expressed as a Fourier series, which is convenient for calculation of interactions. As an example of application the scheme is used to calculate multipole moments and electrostatic interactions between Wigner-Seitz cells in a monoatomic crystal.
 

Physical Review B, 29 5547-53, 1984.