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Mercury crystal structure

Mercury-crystal structure visualisation, exploration and analysis made easy. http //www. ccdc.cam.ac.uk/products/mercury/... [Pg.102]

Fig. 5 shows data from a simulation of TIP4P water that is confined on both sides by a rhombohedral mercury crystal with (111) surface structure. Bosio et al. [135] deduce from their X-ray studies that a solid o-mercury lattice with a larger lattice constant in the z direction may be used as a good structural model for liquid mercury. Thus, the mercury phase was modeled as a rigid crystal in order to simplify the simulations. The surface of such a crystal shows rather low corrugation. [Pg.359]

Zinc dithiocarbamates have been used for many years as antioxidants/antiabrasives in motor oils and as vulcanization accelerators in rubber. The crystal structure of bis[A, A-di- -propyldithio-carbamato]zinc shows identical coordination of the two zinc atoms by five sulfur donors in a trigonal-bipyramidal environment with a zinc-zinc distance of 3.786 A.5 5 The electrochemistry of a range of dialkylthiocarbamate zinc complexes was studied at platinum and mercury electrodes. An exchange reaction was observed with mercury of the electrode.556 Different structural types have been identified by variation of the nitrogen donor in the pyridine and N,N,N, N -tetra-methylenediamine adducts of bis[7V,7V-di- .vo-propyldithiocarbamato]zinc. The pyridine shows a 1 1 complex and the TMEDA gives an unusual bridging coordination mode.557 The anionic complexes of zinc tris( V, V-dialkyldithiocarbamates) can be synthesized and have been spectroscopically characterized.558... [Pg.1196]

In a thorough work with an extensive literature survey, crystal structures, vibrational and 31P NMR spectra of several phosphine complexes of mercury(II) halides HgX2 are presented.235 In the dibenzophosphole complex (dbp)2HgBr2, Hg adopts a distorted tetrahedral coordination (rav(Hg—P) 250.2, rav(Hg—Br) 261.1pm) (cf. the related Cd complex in the previous paragraph), with slightly shorter Hg—P and Hg—Br bonds, respectively, than in the comparable... [Pg.1277]

Vermilion and cinnabar are two bright red, toxic minerals that share an identical composition (they are both composed of mercury sulfide) but have different crystal structures. Two kinds of vermilion are known one of natural origin and another made artificially. Finely ground natural vermilion may vary in hue from red to liver-brown and even to black. Artificial vermilion was made from mercury and sulfur the method of preparation seems to have been developed by the Chinese and was introduced into Europe only during the eighth century c.e. (Gettens et al. 1972). [Pg.97]

Apart from the gold(i) system, bis(mesityl)mercury(ii), which also possesses a heavy metal center with strong relativistic effects, has been used for the synthesis of the mixed metal silver(i) aryl complexes, [HgAg2(mes)X2]2 (X = OTf 13a (Figure 7), C104 13b).33 X-ray crystal structure analysis of 13a revealed its hexanuclear nature with the... [Pg.200]

Similarly, dilithiation of 2-(4-bromophenoxy(ethanol in the presence of magnesium 2-ethoxyethoxide followed by reaction with 0.5 equiv. of HgCl2 afforded the corresponding diarylmercury compound 4-(H0(CH2)20)-C6H4)2Hg 26 whose crystal structure has been determined (Equation (12)).47 In addition to these alcohol and ether derivatives, thio- and phosphinoaryl mercury compounds have also been prepared. Thus, the dilithium salt... [Pg.423]

Also mercury(II) selenite is polymorphic and two new modifications, p-HgSe03 and y-HgSe03, have been recently described.134 They show the mercury atoms in sevenfold coordination of oxygen atoms, and the [I Ig07] polyhedra are linked by the pyramidal selenite ions. A remarkable and unusual mercury selenite is the mixed valent compound (HgSe03)3E[gSe.134 As a characteristic feature, the crystal structure contains [Hg3Se] pyramids with distances Hg Se of 2.489 A. [Pg.363]

An X-ray crystal structure determination of calciferol (vitamin D-2,71) showed that steric crowding in the s-cis diene system resulted in a twisted conformation with a dihedral angle of 53° [59], On irradiation with a mercury lamp, it was partially converted into ergosterol (72) and tachysterol (73) [60, 61]. When a solution of calciferol in light petroleum containing a trace of iodine was exposed to diffuse daylight, the vitamin was photoisomerized to (74) [62],... [Pg.69]

It is known from a variety of crystal structure determinations that the typical interatomic distances d(Hg-Hg) in cationic mercury clusters are significantly smaller ( 250 pm) than in neutral ( 330 pm) and anionic ones ( 300 pm). In a first approximation this is due to a preferred covalent Waals bonding in the neutral (weak) and a preferred Op bonding (medium) in the anionic forms. [Pg.170]

Fig. 2.4-11. The crystal structure of Nal Hg (a) view of the structure emphasizing the centered icosahedral (dark grey) and hexagonal antiprismatic mercury clusters, K atoms outside the clusters are neglected, (b) icosahedral NaHgi2, (c) hexagonal antiprismatic KHg12. Fig. 2.4-11. The crystal structure of Nal Hg (a) view of the structure emphasizing the centered icosahedral (dark grey) and hexagonal antiprismatic mercury clusters, K atoms outside the clusters are neglected, (b) icosahedral NaHgi2, (c) hexagonal antiprismatic KHg12.
Watanabe, Y., Hagihara, H. Crystal structures of mercury ethylxanthate and mercury diethyldithiophosphate. Abstracts international union of crystallography, Kyoto, Japan 1972 (Acta Cryst. B28, 4 (1972)). [Pg.116]

Organolithium compounds, 2 69 ring stacking, 37 82-92 systems capable of, 37 82-83 uncomplexed, structure, 37 53-54 X-ray crystal structure, 37 48 Organomagnesium halides, 2 71 Organomercury compounds, see Mercury, -carbon compounds Organometallic complexes... [Pg.214]

More recent work has yielded another class of carborane-based mercury-containing macrocycles 43 and 44 related to crown ethers such as I2-crown-4 and 9-crown-3. Anticrown 43 associates with one or two moles of lithium halide, depending on conditions. The X-ray crystal structure of the chloride salt is shown in Figure 15. [Pg.313]

The X-ray crystal structures of the related, though less complex, anticrown mercury-containing macrocycles 45 and 46 have also recently been reported. Complex 45 may form either 1 1 complexes with Br or I" or a 3 2 complex with Cr. In the case of the bromo derivative, crystallographic results reveal an infinite chain of alternating Br and 45 with each halide bridging between six Hg atoms, Hg- Br 3.07-3.39 A. It is postulated that the related 3 2 chloride complex exhibits a similar, though finite layered structure. The related pentameric species 46 forms... [Pg.314]


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See also in sourсe #XX -- [ Pg.447 ]




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