:orphan: Converging atoms ================ DIRAC presently does not perform an open-shell Hartree--Fock in a strict sense, rather an average-of-configuration calculation, which amounts to the optimization of the average energy of a set of configurations (or determinants) generated from the specification of a given number of open shells and their electron occupations. In the case of atoms, a convergence problem can occur when the inner open-shell orbitals are more stable than outer "closed" shell. From DIRAC21 onwards, we have atomic supersymmetry and can specify the occupation number of each :math:\kappa value. by using the keyword :ref:SCF_.KPSELE. As examples of such calculations, we consider the Nb and Np atoms. ----------------------------------------------------- Example 1: Nb [Kr]4d\ :sup:4\ 5s\ :sup:1\ ----------------------------------------------------- :: **DIRAC .WAVE FUNCTION .ANALYZE **HAMILTONIAN .X2C **INTEGRALS *READIN .UNCONTRACT **WAVE FUNCTION .SCF *SCF .CLOSED SHELL 18 18 .OPEN SHELL 2 4/10,0 1/2,0 .KPSELE 5 -1 1 -2 2 -3 8 6 12 4 6 0 0 0 4 6 2 0 0 0 0 **ANALYZE .MULPOP *MULPOP .VECPOP 1..oo 1..oo *END OF ---------------------------------------------------------- Example 2: Np [Rn]5f\ :sup:4\6d\ :sup:1\7s\ :sup:2\ ---------------------------------------------------------- :: **DIRAC .WAVE FUNCTION .ANALYZE **HAMILTONIAN .X2C **INTEGRALS *READIN .UNCONTRACT **WAVE FUNCTION .SCF *SCF .CLOSED SHELL 44 44 .OPEN SHELL 2 4/0,14 1/10,0 .KPSELE 7 -1 1 -2 2 -3 3 -4 14 10 20 12 18 6 8 0 0 0 0 0 6 8 0 0 0 4 6 0 0 **ANALYZE .MULPOP *MULPOP .VECPOP 1..oo 1..oo *END OF