The structures of [Cu(AA)(6)](ClO(4))(2), (I), and [Mn(AA)(6)](ClO(4))(2), (II) (AA is acrylamide, also known as prop-2-enamide; C(3)H(5)NO), display both intra- and intermolecular N-H...O hydrogen bonding. A three-dimensional network is propagated via the perchlorate counter-ions. There are two crystallographically independent molecules in the copper complex, with the most significant difference between them being the conformation of one symmetry-related pair of AA ligands which are in the unusual syn conformation. The copper complex exhibits syn/anti disorder of the =CH(2) group in one pair of symmetry-related AA ligands. The Cu(II) and Mn(II) centres are both situated on centres of inversion. The copper complex cation has octahedral coordination geometry with typical Jahn-Teller distortions.