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Crystallographic elements

Other relationships between crystallographic elements of symmetry and interhelical parameters can be easily derived. [Pg.286]

Ferric Orthoarsenite, FeAs03, was described by Reichard 9 as a rust-yellow powder obtained by adding potassium tetrarsenite to a dilute aqueous solution of ferric chloride. A substance of similar chemical composition has been found in a crystalline deposit formed during the Deacon process of making chlorine. The crystals of the pure salt are monoclinic, their crystallographic elements being 10... [Pg.167]

System Crystallographic elements Essential symmetry Number of point groups... [Pg.455]

Cobalt Arsenates.—The ortho-arsenate, Co3(As04)2.8IT20, occurs in nature as erythrite or cobalt bloom in the form of monoclinic crystals isomorphous with vivianite, Fes(P04)2.8lI20, and perhaps with nickel ochre, Ni3(As04)z.8H20. Its crystallographic elements are ... [Pg.65]

Calcium Platinocyanide, CaPt(CN)4.5H20, may be prepared in a similar manner to the barium salt.3 It crystallises in rhombic prisms, having the following crystallographic elements 4 ... [Pg.321]

Rubidium Platinocyanide,5 Rb2Pt(CN)4.3H O ( ) yields monoclinic crystals, the crystallographic elements being ... [Pg.324]

On concentration the salt separates out as long triclinic prisms 3 closely resembling in properties the potassium salt. The crystallographic elements are ... [Pg.325]

Sodium Potassium Platinocyanide, NaKPt(CN)4.3H20, results when the copper salt is decomposed with a mixed solution of sodium and potassium carbonates.4 It crystallises in beautiful orange-coloured monoclinic prisms, and closely resembles the barium potassium salt. Its crystallographic elements are 3 ... [Pg.325]

Strontium Platinocyanide, SrPt(CN)4.5H20, is most easily obtained by boiling the copper derivative with aqueous strontium hydroxide.4 The crystals form monoclinic tablets, milky white in colour, but exhibiting a delicate violet surface-tint and a green fluorescence. The crystallographic elements 3 are ... [Pg.325]

Marcasite or white iron pyrites is the name given to a rhombic variety of pyrites which occurs m concretions, known locally as fairy balls and thunderbolts. Its crystallographic elements"are 5... [Pg.22]

Copper pyrites or chalcopyrite, Cu2S.Fe2S3, is a brass-coloured sulphide which crystallises in the tetragonal system, but is isomorphous with pyrites, since its crystallographic elements are 8... [Pg.23]

Vivianite,8 Fe3(P04)2.8H20, occurs as monoclinic crystals, isomor-phous with erythrite, Co3(As04)2.8H20, and perhaps also with anna-bergite, Ni3(As04)2.8H20. Its crystallographic elements are —... [Pg.26]

An anhydrous mixed phosphate of manganese, calcium, and divalent iron occurs as Graftonite, (Fe, Mn, Ca)3(P04)2, which occurs as salmon-coloured, monoclinic crystals, the crystallographic elements of which are... [Pg.26]

Sodium ferric metasilicate is found as acmite7 or aegirite,8 Na2Fe2(Si03)4. Its crystals are blackish green in colour, and possess the following crystallographic elements —9... [Pg.28]

The decahydrate, Fe2(SO4)3.10H2O, occurs in nature as quenstedtite, in monoclmic crystals, the crystallographic elements being —1... [Pg.160]

The salt yields green crystals, readily soluble in water. They belong to the triclinic system, their crystallographic elements being as follow —4... [Pg.167]

The salt separates out in hydrated crystals, which are usually pale violet in colour, the extent of hydration varying according to circumstances. Two definite hydrates are known6 namely, the nonahydrate,6 Fe(N03)3.9H20, which yields pale red deliquescent monoclinic crystals,7 of the following crystallographic elements —... [Pg.176]

The tetra-ethyl salt is likewise triclinic, possessing the following crystallographic elements —2... [Pg.181]

The anhydrous salt has been found as a deposit m the Deacon process for the preparation of chlorine, in the form of black prismatic crystals, belonging to the monoclmic system. Its crystallographic elements are —... [Pg.193]

The hernhydrate, (NHi),W40i3.6II.,0, is formed by treating a hot solution of the salt with alcohol and allowing the mixture to cool, when it separates in nionoclinic prisms. Its crystallographic elements are... [Pg.238]

Figure 2.12 Models of packing of the stable form of iPS (a) [40] and form I of iPB (b) [45], with chains in 3/1 helical conformation packed in trigonal lattices according to the space groups R3c or R3c. Some crystallographic elements of symmetry for the space groups R3c or 7 3c are also indicated. Figure 2.12 Models of packing of the stable form of iPS (a) [40] and form I of iPB (b) [45], with chains in 3/1 helical conformation packed in trigonal lattices according to the space groups R3c or R3c. Some crystallographic elements of symmetry for the space groups R3c or 7 3c are also indicated.
See other pages where Crystallographic elements is mentioned: [Pg.8]    [Pg.134]    [Pg.200]    [Pg.204]    [Pg.320]    [Pg.324]    [Pg.166]    [Pg.170]    [Pg.192]    [Pg.8]   
See also in sourсe #XX -- [ Pg.46 , Pg.47 ]

See also in sourсe #XX -- [ Pg.46 , Pg.47 ]



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