Znln2Se4 polycrystalline samples were synthesized with small amounts o
f manganese and their optical absorption spectra examined. It was foun
d that pure material shows the presence of defect states very close to
the conduction and valence bands; however, the presence of manganese
atoms reduces the density of defects and, at 0.3 at% of Mn, the defect
states located very close to the conduction and valence bands are eli
minated. The observed results are explained by considering that the Mn
atoms tend to occupy the Zn vacancy sites and reduce antisite-induced
disorder.