FRACTIONAL OCCUPATION NUMBERS AND DENSITY-FUNCTIONAL ENERGY GRADIENTSWITHIN THE LINEAR COMBINATION OF GAUSSIAN-TYPE ORBITALS APPROACH

Gradients of the total energy with respect to nuclear displacements us ing fractionally occupied orbitals within a linear combination of Gaus sian-type orbitals density-functional theoretical approach are discuss ed. Expressions for the gradient in the fractional occupation number s olution as well as for Fermi and Gaussian broadening are presented and related to preciously described methods.