  The computation of light scattering by the superposition T-matrix scheme has
been so far restricted to systems made of particles that are either sparsely
distributed or of near-spherical shape. In this work, we extend the range of
applicability of the T-matrix method by accounting for the coupling of
scattered fields between highly non-spherical particles in close vicinity. This
is achieved using an alternative formulation of the translation operator for
spherical vector wave functions, based on a plane wave expansion of the
particle's scattered electromagnetic field. The accuracy and versatility of the
present approach is demonstrated by simulating arbitrarily oriented and densely
packed spheroids, for both, dielectric and metallic particles.
