CeHg3 was found to undergo an antiferromagnetic phase transition at 1.
6 K. This was indicated by the lambda-type peak in its heat capacity a
nd a negative paramagnetic Curie temperature. The electronic specific
heat coefficient gamma of 52 mJ/mol K-2 suggested that CeHg3 is not a
heavy fermion material contrary to its isostructural counterpart CeAl3
.