  We present a variant of the recently developed quantum corrected model (QCM)
for plasmonic nanoparticles [Nature Commun. 3, 825 (2012)] using non-local
boundary conditions. The QCM accounts for electron tunneling in narrow gap
regions of coupled metallic nanoparticles, leading to the appearance of new
charge transfer plasmons. Our approach has the advantages that it emphasizes
the non-local nature of tunneling and introduces only contact resistance, but
not ohmic losses through tunneling. Additionally, it can be implemented much
easier in boundary element method (BEM) approaches. We develop the methodology
for the QCM using non-local boundary conditions, and present simulation results
of our BEM implementation which are in good agreement with those of the
original QCM.
