[Pw_forum] about superposition of atomic rho and atomic wfc's

[Reza Ebraahimi]

Hi
I am new with pwscf, so sorry if my question seems basic to you!
i have noticed that the code calculates the superpositon of charge density and wfc's from atomic configurations by two subroutines: "atomic_rho.f90" and "atomic_wfc.f90". Could anyone refer me to a text or something to know exactly what happens in these two( i mean mathematically)?
And i thought that we need the superposition of charge density from atomic configuration to build up the KS Hamiltonian( with the knowledge of n(r) ) and obtain the solid wfc's by diagonalizing it at the first iteration. Why do we need the superposition of wfc's from atomic configuration?
Thank You


      
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