  The \b{eta}-decay of 100 Tc has been studied using the Total Absorption
{\gamma}-Ray Spectroscopy technique at IGISOL. In this work the new DTAS
spectrometer in coincidence with a cylindrical plastic \b{eta} detector has
been employed. The \b{eta}-intensity to the ground state obtained from the
analysis is in good agreement with previous high-resolution measurements.
However, differences in the feeding to the first excited state as well as weak
feeding to a new level at high excitation energy have been deduced from this
experiment. Theoretical calculations performed in the quasiparticle random-
phase approximation (QRPA) framework are also reported. Comparison of these
calculations with our measurement serves as a benchmark for calculations of the
double \b{eta}-decay of 100 Mo.
