Only applies if LCAOAlternative = true, and all species are pseudopotentials. (experimental) If this variable is set to yes, the LCAO procedure will add an extra set of numerical orbitals (by using the derivative of the radial part of the original orbitals). Note that this corresponds roughly to adding orbitals with higher principal quantum numbers, but the same angular momentum. This option may cause problems for unoccupied states since you may miss some lower-lying states which correspond to higher angular momenta instead of higher principal quantum number.
scf/lcao.F90 : 519
call parse_variable(namespace, 'LCAOExtraOrbitals', .false., this%derivative)