Density matrix Redfield equation solutions

The preceding derivation of an expression for l/Tj, equation (29), was for a simple case with two eigenstates and only one interaction V. A more general case will involve further simultaneous equations, and relaxation times that depend on more than one integral of type Such cases can often be made more tractable by replacing expression (19) with a density matrix, whose elements are the averaged products C C . In this representation the wave equation converts to an equation involving this matrix. Its solution was first studied by Kubo and Tomita, and then developed by Redfield and many others. Their approach is essential in complex... 

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