The Rayleigh-Ritz variational method is used with multiconfigurationinterraction wave function and restricted variation method to obtain the energies of 1s~22s~2p()~1P~o,1s~22s~2p()~3P~0,and 1s~22p~2()~3P states in berylliumlike CⅢ and OⅤ,including the mass polarization and relativistic corrections.
Next we settle the remaining cases, with a computer-aided variation on the old method of Donkin.
Implementing this point of view, Poisson Summation Formulas are proved in several spaces including integrable functions of bounded variation (where the result is known) and elements of mixed norm spaces.
We construct a sharp criterion for the existence of absolutely continuous solutions of bounded variation.
Boundary-variation solution of eigenvalue problems for elliptic operators
A theorem of Fejér states that if a periodic function F is of bounded variation on the closed interval [0, 2π], then the nth partial sum of its formally differentiated Fourier series divided by n converges to π-1[F(x+0)-F(x-0)] at each point x.