Crystalline system Monoclinic

Hydrozincite is anhydrous carbonates. The crystalline system is monoclinic-prismatic with the space group C2/m. The structure is composed of Zn in both octahedral and tetrahedral coordination, in the ratio 3 2. The octahedral Zn atoms form part of a C6 type sheet with holes. The octahedral Zn atoms occur above and below these holes. The natural hydrozincite in our study consisted of three samples. Concentrations of potential luminescent impurities are presented in Table 4.13. The laser-induced time-resolved technique enables us to detect Pb center (Fig. 4.37). 

Strongly refractive, crystalline mass (monoclinic system). d1 4 6. Sublimes above 600s. Solubility in water (2(7) ].32 g/100 ml. Does not react with water forms stable tri-hydrate. Freely soluble in hydrofluoric acid. LDU in mice 98 mg/kg orally Toxic Substances List. H. E. Christensen, Ed. (1972) p 547. 

Primitive three-dimensional lattices have been classified into seven crystalline systems triclinic, monoclinic, orthorombic, tetragonal, cubic, trigonal, and hexagonal. They are different in the relative lengths of the basis vectors as well as in the angles they form. An additional seven nonprimitive lattices, belonging to the same crystalline systems, are added to the seven primitive lattices, which thus completes the set of all conceivable lattices in ordinary space. These 14 different types of lattices are known as Bravais lattices (Figure 3). 

Fig. 1. Orientation of crystalline magnetic tensors in Fig. 2. Orientation of crystalline magnetic tensors in triclinic system. monoclinic system.

Hydrozincite is anhydrous carbonates. The crystalline system is monoclinic-prismatic with the space group C2/m. The structure is composed of Zn in both octahedral and tetrahedral coordination, in the ratio 3 2. The octahedral Zn atoms... 

Sulfur crystallizes in at least two distinct systems the rhombic and the monoclinic forms. Rhombic sulfur, Sa, is stable at atmospheric pressures up to 95.5°C, at which transition to monoclinic sulfur, SP, takes place. Monoclinic sulfur is then stable up to its natural melting point of 114.5°C. The basic molecular unit of both of these crystalline forms of sulfur is the octatomic sulfur ring Other forms of sohd sulfur include hexatomic sulfur as well as... 

SOAz (II) This second crystalline form adopts the monoclinic system, systematic reflection absences indicating P2j/c as the space group. The volume of the cell is twice that of SOAz (I), indicating that the two crystallographically independent... 

Anhydrous lithium carbonate forms a voluminous white powder both A. Arfvedson1 and L. Kralowansky obtained the salt in a crystalline form, and by evaporating a soln. sat. at 15°, F. C. Fliickiger obtained long prisms which, according to E. Mallard, belong to the monoclinic system, with axial ratios orb c=l 672 1 1244, and /J=114° 25. The fused salt also furnishes a mass... 

The properties of ammonium hydrocarbonate.—Ammonium hydrocarbonate occurs in the form of a powder, in transparent or opalescent crystals, and in translucent crystalline masses. The crystals have been measured by H. Rose, W. H. Miller, H. St. C. Deville, C. F. Rammelsberg, F. Riidorff, etc. they belong to the rhombic system, and have the axial ratios a b c— 0 6726 1 0 3998. H. Rose claimed to have once made monoclinic crystals of ammonium hydrocarbonate, isomorphous with the potassium salt, by evaporating a soln. of the normal salt in vacuo, but this observation has not been confirmed. In his 1852 paper, H. St. C. Deville stated that he believed that he had prepared crystals of the hydrocarbonate belonging to a different system to the ordinary salt, but in his 1854 paper he attributed little weight to this observation, and stated only one hydrocarbonate exists, but since the crystalline form of this salt is not isomorphous with the corresponding potassium hydrocarbonate, he stated that both these salts will prove one day to be dimorphous, implying that the unknown form of the one carbonate will prove to be isomorphous... 

Its crystals belong to the monoclinic system. The product used in industrial practice should be crystalline in form and be easily pourable into a mould for compression. According to Davis [21] a product with mixed, i.e. relatively large and small crystals (Fig. 5), is best suited for this purpose. 

As already described, other crystalline forms of arsenic besides the rhombohedral are known or suspected to exist. The crystals of the yellow allotrope belong to the cubic system, while native arsenolamprite (p. 8) contains crystals belonging to the rhombic, or possibly to the monoclinic, system. Yellow arsenic is soluble in carbon disulphide. 

HESSITE. A mineral telluride of silver. AgyTe. with some gold, crystallizing in the monoclinic syslem at normal temperatures isometric system above I49.5F (65.3 C). Crystalline form not ohvious at normal temperatures. Hardness. 2-3 specific gravity. 8.24-8.45 color, gray with metallic luster opaque. Named after G.H. Hess (1802— 1850). 

The crystals were needle-shaped or tabular, in the monoclinic system. The corresponding potassium salt, KsPS4, was obtained as a yellow crystalline mass by fusing KC1 with P2S6. 

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