Hermitian R matrix in the presence of first-derivative couplings

In formulations of scattering theory which use an expansion in adiabatic eigenfunctions, such as the perturbed-stationary-state approximation, the coupled-channel equations include derivative couplings. The R matrix is not Hermitian in regions where the derivative couplings are nonzero. It is shown that a superposition of the logarithmic derivative matrix and the derivative coupling matrix is Hermitian.