We report the integral elastic cross section for low-energy electron scatte
ring by the boron trihalides BCl3, BBr3, and BI3. To perform our calculatio
ns, we employed the Schwinger multichannel method with pseudopotentials. We
have focused our attention only in the B-2 irreducible representation, whe
re we found shape resonances for the three molecules in a previous static-e
xchange calculation, at energies below 5 eV. We included polarization effec
ts to improve the description of the resonances and found that only the res
onance for BCl3 remains. For BBr3 and BI3, the resonances become bound stat
es.