  We develop a unified theory of plasmon-assisted resonance energy transfer
(RET) between molecules near a metal nanostructure that maintains energy
balance between transfer, dissipation, and radiation. We show that in a wide
range of parameters, including in the near field, RET is dominated by
plasmon-enhanced radiative transfer (PERT) rather than by a nonradiative
transfer mechanism. Our numerical calculations performed for molecules near the
Ag nanoparticle indicate that RET magnitude is highly sensitive to molecules'
positions.
