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Hg Atom (hg + atom)

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Chemistry100%

Selected Abstracts

The layered compound poly[,2 -4,4,-bipyridyl-di-,2 -chlorido-mercury(II)]

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2007
Yi-Ming Xie
The title compound, [HgCl2(C10H8N2)]n, features two-dimensional [HgCl2(4,4,-bipy)]n neutral networks (4,4,-bipy is 4,4,-bipyridine), based on an octahedral Hg atom coordinated by four ,2 -Cl atoms and two ,2 -4,4,-bipy ligands in trans positions, yielding a HgCl4N2 octahedron. The structure has mmm symmetry about the Hg atoms, with most of the atoms on at least one mirror plane, but the unsubstituted C atoms of the 4,4,-bipy rings are disordered across a mirror plane. Photoluminescent investigations reveal that the title compound displays a strong emission in the green region, which probably originates from a ligand-to-ligand charge-transfer transition. [source]

Manganese mercury thio­cyanate (MMTC) glycol mono­methyl ether

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2000
Dong Xu
In the title complex, [MnHg(NCS)4(C3H8O2)]n, each Hg atom is tetrahedrally coordinated with four S atoms of the SCN, ions, and each Mn atom is octahedrally coordinated with four N atoms of the SCN, ions, one hydroxyl O atom and one ethereal O atom of the glycol mono­methyl ether mol­ecule. Each pair of Hg and Mn atoms is bridged by one SCN, ion. A 24-membered Mn3Hg3(SCN)6 ring is formed as the strucrural unit, with the six metal atoms in a chair-form hexagonal arrangement. The units are condensed and linked three-dimensionally in the crystal resulting in a diamond-like structure. [source]

Atomic resolution structure of Escherichia coli dUTPase determined ab initio

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2001
A. González
Cryocooled crystals of a mercury complex of Escherichia coli dUTPase diffract to atomic resolution. Data to 1.05,Å resolution were collected from a derivative crystal and the structure model was derived from a Fourier map with phases calculated from the coordinates of the Hg atom (one site per subunit of the trimeric enzyme) using the program ARP/wARP. After refinement with anisotropic temperature factors a highly accurate model of the bacterial dUTPase was obtained. Data to 1.45,Å from a native crystal were also collected and the 100,K structures were compared. Inspection of the refined models reveals that a large part of the dUTPase remains rather mobile upon freezing, with 14% of the main chain being totally disordered and with numerous side chains containing disordered atoms in multiple discrete conformations. A large number of those residues surround the active-site cavity. Two glycerol molecules (the cryosolvent) occupy the deoxyribose-binding site. Comparison between the native enzyme and the mercury complex shows that the active site is not adversely affected by the binding of mercury. An unexpected effect seems to be a stabilization of the crystal lattice by means of long-range interactions, making derivatization a potentially useful tool for further studies of inhibitor,substrate-analogue complexes of this protein at very high resolution. [source]

The structure of orange HgI2.

ACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2002

The metastable orange crystals of HgI comprise three different crystal structures all of which are built from corner-linked HgI supertetrahedra. Two of the structures are end members with the maximum degree of order (MDO) of a polytypic layer structure. In this paper, the third structure (D) determined from X-ray diffraction, a crystal chemical discussion of the four known tetrahedral HgI structures, and a twinning model are presented. All the various diffraction results published during the past 70 years are now explained. The HgI supertetrahedra of the tetragonal structure D are corner-linked into two interpenetrating diamond-type networks. The stable red form and the three orange structures show the same cubic densest packing of I atoms and differ only in the distribution of Hg atoms in the tetrahedral voids. Transformations between the structures may involve only movements of Hg atoms, as implied by larger thermal displacement parameters of Hg than of I. A multiply twinned conglomerate of MDO1, MDO2 and D, each structure occurring in three orientations, results in metrically cubic crystals whose Bragg reflections are very close to reciprocal lattice points. [source]

The layered compound poly[,2 -4,4,-bipyridyl-di-,2 -chlorido-mercury(II)]

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2007
Yi-Ming Xie
The title compound, [HgCl2(C10H8N2)]n, features two-dimensional [HgCl2(4,4,-bipy)]n neutral networks (4,4,-bipy is 4,4,-bipyridine), based on an octahedral Hg atom coordinated by four ,2 -Cl atoms and two ,2 -4,4,-bipy ligands in trans positions, yielding a HgCl4N2 octahedron. The structure has mmm symmetry about the Hg atoms, with most of the atoms on at least one mirror plane, but the unsubstituted C atoms of the 4,4,-bipy rings are disordered across a mirror plane. Photoluminescent investigations reveal that the title compound displays a strong emission in the green region, which probably originates from a ligand-to-ligand charge-transfer transition. [source]