Formation of NH4[Hg-3(NH)(2)](NO3)(3) and transformation to [Hg2N](NO3)

NH4[Hg-3(NH)(2)](NO3)(3) (1) and [Hg2N](NO3) (2) are obtained from cone. aqueous ammonia solutions of Hg(NO3)(2) at ambient temperature and under hydrothermal conditions at 180 degreesC, respectively, as colourless and dark yellow to light brown single crystals. The crystal structures {NH4[Hg-3(NH)(2)](NO3)(3): cubic, P4(I)32, a = 1030.4(2) pm, Z = 4, R-all = 0.028; [Hg2N](NO3): tetragonal, P4(3)2(1)2, a = 1540.4(1), c = 909.8(1) pm, Z = 4, R-all = 0.054} have been determined from single crystal data. Both exhibit network type structures in which [HNHg3] and [NHg4] tetrahedra of the partial structures of 1 and 2 are connected via three and four vertices, respectively. 1 transforms at about 270 degreesC in a straightforward reaction to 2 whereby the decomposition products of NH4NO3 are set free. 2 decomposes at about 380 degreesC forming yellow HgO. Most certainly, I is identical with a mineral previously analyzed as

Electrochemistry of Hg(II) Salts in Room-Temperature Ionic Liquids

The electrochemistry of HgCl(2) and [Hg(NTf(2))(2)] ([NTf(2)](-) = bis-{(trifluoromethyl)sulfonyl}imide) has been studied in room temperature ionic liquids. It has been found that the cyclic voltammetry of Hg(II) is strongly dependent on a number of factors (e.g., concentration, anions present in the mixture, and nature of the working electrode) and differs from that found in other media. Depending on conditions, the cyclic voltammetry of Hg(II) can give rise to one, two, or four reduction peaks, whereas the reverse oxidative scans show two to four peaks. Diffuse reflectance UV-vis spectroscopy and X-ray powder diffraction have been used to aid the assignment of the voltammetric waves.

HG 186.9-187.0 D.E-1

Coarse grained sediment with a few fine grained matrices. Brown sediment with small to medium sized clasts. Clasts range from sub-angular to sub-rounded. Organic material present.

HG 186.9-187.0 D.E-2

Coarse grained sediment with small patches of a fine grained domain. The domain may contain organic material. Lineations and minor grain stack present throughout the section.

HG 186.9-187.0 D.E-3

Fractured and weathered grains throughout the section. Lineations and grain stacks throughout the section.

HG 186.9-187.0 D.E-4

Fine grained domain within a coarse grained domain. Lineations throughout the section. A few small patches of a clay domain seen towards the top left.

HG 186.15-186.25-1

Coarse grained section with two different fine grained domains. Towards the left hand side the domain is dark and has no inclusions of coarse grains. The right hand side has some coarser materials.

HG 186.15-186.25-2

Major grains crushing towards the top left with two fine grained domains in coarse grained sediment.

HG 186.15-186.25-3

Major grain crushing towards the centre of the section. A few lineations and grain stacks also present.

HG 186.55-186.75-1

Domain boundaries observed between the fine grained and coarse grained sediment. The coarse grained sediment contains lineations.

HG 186.55-186.75-2

Fine grained sediment, quite structure-less.

HG 186.15-186.25 Thin Section

Coarse grained sample with multiple fine grained domains. Clasts range from small to medium and sub-angular to sub-rounded. Mainly contains grain crushing (with grains crushed into one another) and short distance lineations. A few rotation structures are seen and fine grained sand domains can also be seen.

HG 186.80-186.85 Thin section

A coarse grained sample with clay rich domains. Grains range from small to medium and are sub-angular. Rotation structures can be seen around sub-rounded clasts. Lineations can be seen throughout the image, mainly short distance lineations. Small comet structures can also be seen throughout the images.

HG 186.9-187.0 D.E.

Coarse grained sediment with a few fine grained matrices. Brown sediment with small to medium sized clasts. Clasts range from sub-angular to sub-rounded. Organic material present. It contains rotation structures throughout as well as edge-to-edge grain crushing. Fine grained clay domains are present and lineations can also be seen. Minor amounts of grain stacking can also be seen.

HG 186.9-187.0 D.E. Thin Section

Coarse grained sample with grains varying from small to medium in size. They range from sub-angular to sub-rounded in shape. The sample is abundant in lineations and comet structures. Minor amounts of grain stacking are present. Inclusions of a clay rich, fine grained domain.