Minimization principles of linear response eigenvalue problems Zhaojun Bai University of California, Davis Linear Response (LR) eigenvalue problems arise from excitation state calculations in the study of collective motion of many particle systems. There are a great deal of recent work and interests in developing efficient simulation techniques for excitation state calculations of molecules for materials design in energy science. In this talk, we will first present minimization principles of LR eigenvalue problems and then discuss the development of conjugate gradient-like algorithms for simultaneously computing the smallest eigenvalues with positive sign. Finally, we present numerical results of large-scale LR eigenproblems for calculating excitation states of molecules. This is a joint work with Ren-cang Li, Dario Rocca and Giulia Galli.