Influence of anion substitution on hydrogen-bonding patterns of salt compounds: cytosinium hydrogen sulfate and cytosinium perchlorate

Abstract

In the two title compounds, cytosinium hydrogen sulfate, C(4)H(6)N(3)O(+).HSO(4)(-), (I), and cytosinium perchlorate, C(4)H(6)N(3)O(+).ClO(4)(-), (II), the asymmetric units comprise a cytosinium cation with hydrogen sulfate and perchlorate anions, respectively. The crystal structures of (I) and (II) are similar; that of (I) is characterized by a three-dimensional N-H...O, O-H...O and C-H...O hydrogen-bonded network. In (I) and (II), two-dimensional layers are formed by N-H...O and C-H...O hydrogen bonds and, in the case of (I), they are linked by O-H...O hydrogen bonds where the anion acts as a donor and the cation as an acceptor. The hydrogen-bonded sheets in (II) form an angle of 87.1 degrees.