A wave packet approach to the Liouville–von Neumann equation for dissipative systems

摘要: A method for the numerical solution of dissipative Liouville–von Neumann equation is presented. The reduced density operator expanded in a basis time-dependent wave functions. This guarantees that size required representation minimal. Equations motion expansion functions and matrix elements are obtained from Dirac–Frenkel variational principle. effort scales proportional to N, where N dimension relevant Hilbert space. As first example, dynamics three-mode system with vibronic coupling (with N≈50 000) coupled bath has been studied, modeling S1/S2 states pyrazine. For cw-absorption spectrum, fast convergence respect number obtained.