# JuliaAtoms

Welcome to JuliaAtoms!

The JuliaAtoms GitHub organisation collects a few Julia packages that are useful for calculations within Atomic Physics.

At the moment, the following packages are available (all of them under development, i.e. no stability promised yet):

A library used to define electronic configurations constructed from electronic orbitals in spherical symmetry.

Data structures for representing atoms in a product space of orbitals and a radial grid. The radial grid can be any implementation of the ContinuumArrays.jl interface, but AtomicStructure.jl has only been tested with CompactBases.jl so far. It also contains a submodule for the solution of integro-differential eigenproblems, in a self-consistent manner, as well as using manifold optimization routines from Optim.jl.

A library for setting up the energy expression of a system built up from a set of configurations. At the moment, the implementation is geared towards atomic systems (in that it uses data structures from AtomicLevels.jl), but it is applicable to other systems as well, such as molecules.

A library for the special case of energy expressions in spherical symmetry, but more importantly, also the computation of tensor matrix elements between spin-orbitals.

Contains some of the analytically known results for atomic hydrogen, or more generally, a one-electron system in spherical symmetry.

A library that implements the calculation of the Coulombic repulsion between pairs of electrons, also known as the Slater integrals.

As mentioned above, the radial problem is implemented using

This library implements various basis sets of compact support, such as finite-difference, finite-element discrete-variable representation, and B-splines, all with their respective benefits and drawbacks for discretization of partial differential/integro-differential equations.