ErPt2Si2(CaBe2Ge2 structure type) has been shown to remain paramagneti
c down to 1.5 K. From the analysis of the slow relaxing Mossbauer spec
tra observed in the paramagnetic state it was concluded that the Er mo
ment associated with the ground state amounts to 8.25(20)mu(B). This v
alue is very close to the full moment of 9mu(B) for Er3+ ions.