  We present a statistical mechanics approximation scheme for the explicit
treatment of spacer-mediated configurational correlations among the mesogenic
units that form a dimer molecule. The approximation is applied to the
description of the nematic phase of linear uniaxial dimers interacting via a
standard molecular pair-potential. Transition temperatures, order parameters
and pair correlation averages are calculated for different spacer lengths. The
results readily reproduce the experimentally observed trends of phase
transition thermodynamics and of dipolar correlations deduced from dielectric
studies.
