Abstract
Complementary variational methods for the solution of a general equation are developed. It is shown that these lead to upper and lower bounds for the second order energy of Rayleigh-Schrodinger perturbation theory for both the ground and a general excited state. The theory may also be applied to the time dependent perturbative calculation of dynamic polarizabilities at real frequencies and upper and lower bounds are derived for any nonresonant value of the frequency. Illustrative calculations are presented.

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