Two-photon spectroscopy of $1D^-$-dissipative tunneling in quantum molecules with $D^-$-centers

Theoretical investigation of the electric field influence on tunnel process in quantum molecule with $D^-$-center is fulfilled in one - instanton approximation. It is shown, that the presence of electric field leads to the double - well transformation, and, as consequence, to appearance of the resonance peak on the tunnel probability field dependence, when the double - well oscillator potential become a symmetric one. It is found, than such feature can be identified in spectra of two - photon impurity absorption.