Comments on the classical theory of energy transfer. II. Extension to higher multipoles and anisotropic media

The classical electromagnetic theory of the fluorescence emission and energy transfer in layered systems is extended to describe magnetic dipole and electric quadrupole radiation and anisotropic media. A general formulation is developed for energy transfer from various emitter types and orientations to isotropic acceptors. The description is exact within the classical framework and requires none of the usual assumptions as to the nature of the acceptor layer. The theory is further extended to describe one‐ and two‐dimensional acceptors and electric dipole radiation in an anisotropic medium. The latter case is the actual situation in the fatty‐acid layer experiments. The coupling to the surface plasmon modes of the acceptor is discussed as it relates to the various systems described here.