> Dear users, > > After reading the siesta papers, I clearly understand the concept of > atomic-like orbitals (radial function times spherical harmonics). However, > I don't quite understand the phrase "the radial shape of every orbital is > numerical." Can someone kindly give me a simple explanation?
This means, it is an (in principle) arbitrary function given on a disretzed radial mesh, without any specfically enforced analytic properties (like e.g. Gaussians, Slater orbitals, polynomials, etc.) Best regards Andrei Postnikov
