title: catena-Poly[[dichloridomercury(II)]-N'-nicotinoylnicotinohydrazide].
abstract: The title complex, [HgCl(2)(C(12)H(10)N(4)O(2))](n), is composed of one Hg(II) ion, one nnh ligand (nnh = N'-nicotinoylnicotinohydrazide) and two coordinated chloride ions. The Hg(II) ion shows a distorted tetra-hedral geometry, being surrounded by two N atoms from two nnh ligands and two chloride ions. Due to the bridging role of nnh, the Hg(II) atoms are connected into polymeric chains along the c axis, which are further inter-linked via N-H⋯O and C-H⋯Cl hydrogen-bonding inter-actions, forming a three-dimensional network.
authors.affiliation: College of Pharmacy, Nanjing Medical University, Nanjing 210029,  People's Republic of China.
authors.forename: Teng
authors.initials: T
authors.lastname: Ma
authors.forename: Yuanlu
authors.initials: Y
authors.lastname: Wang
authors.forename: Fengliang
authors.initials: F
authors.lastname: Wang
authors.forename: Fei
authors.initials: F
authors.lastname: Li