A redetermination of the crystal structure of mercury(I) nitrate dihydrate

Metal (Li, K, SnII and HgII) complexes of the 1,3-diazaallyl [N(R)C(Ph)NC(Ph)CR2]− (R = SiMe3)

“…The crystalline compound [Hg(L-LЈ) 2 ] 4 is a monomer in which the metal atom is bonded in a linear fashion to the terminal nitrogen atoms of two different 1,3-diazaallyl ligands [N(1)-Hg-N(3) 176.6(4)]; the Hg-N bond distances to these nitrogen atoms, of 2.07(1) and 2.08(1) Å, are within the range for typical covalent Hg-N single bonds as observed in 9 while the contacts to the internal nitrogen atoms N(2) and N(4) are much longer, 2.70(1) and 2.61(1) Å respectively, and thus represent at best only weak interactions. Similar bond lengths [Hg-N 2.069(6), 2.071(7) and 2.721(7), 2.717(7) Å, respectively] have been reported for the related benzamidinate [Hg{N(R)C(Ph)NR} 2 ].…”

Crystal chemistry of compounds containing mercury in low oxidation states

“…In the crystal structure of Hg 2 (NO 2 ) 2 , the molecules are packed in a herringbone fashion. 7,8 The structure of this compound was also studied by Ohba and coworkers. 17 In this study, the Hg_O bond (2.577 # A) was found along with the Hg7O (2.24 # A) bond, i.e., both oxygen atoms of the NO À 2 group are bound to the mercury atoms of the (Hg7Hg) 2+ cations to form a planar centrosymmetrical molecule.…”

“…2H 2 O. 8 What the crystal structures of the two known mercurous vanadates, viz., HgVO 3 and the mixed-valence Hg 2 VO 4 , have in common is a distorted five-vertex coordination polyhedron about the vanadium formed by the oxygen atoms. 19 In both structures, the polyhedra of the vanadium atoms are linked via shared edges to form infinite [(VO 3 ) 7 ] n chains.…”

“…Analogous linear groups were found in the structures of hydrates Hg 2 (NO 3 ) 2 . 2H 2 O, 7,8 Hg 2 SiF 6 . 2H 2 O (see Ref.…”

“…2H 2 O. 7,8 Originally, 7 the coordination environment about the mercury atoms in the (Hg 2 ) 2+ pairs was described as a tetrahedron. The rather short distance between the mercury atom and the oxygen atom of the water molecule is indicative of the formation of the aqua [H 2 O7Hg7Hg7OH 2 ] 2+ cations.…”