Electron collisions with $\alpha$-D-glucose and $\beta$-D-glucose monomers

The development of new alternative routes for production of second generation ethanol from sugarcane biomass poses a challenge to the scientific community. Current research in this field addresses the use of a plasma-based pretreatment of the lignocellulosic raw material. With the aim to provide a theoretical background for this experimental technique we investigate the role of low-energy electrons from the plasma in the rupture of the matrix of cellulosic chains. In this paper we report calculated cross sections for elastic scattering of low-energy electrons by the $\alpha$- and $\beta$-D-glucose monomers. The calculations employed the Schwinger multichannel method with pseudopotentials and were carried out at the static-exchange and static-exchange plus polarization levels of approximation. Resonant structures appearing at different energies for $\alpha$-and $\beta$-glucose at the low-energy regime of impact energies can be understood as a fingerprint of an ``isomeric effect'' and suggest that distinct fragmentation mechanisms proceeding {\it via} $\sigma^{*}$ shape resonances may become operative depending on the glucose anomer under consideration.