Cesium chloride CsCl

Figure 1.7 The structures of crystalline sodium chloride (NaCI), cesium chloride (CsCl), and zinc sulfide (ZnS).

In most ionic crystals, the anion is larger than the cation and, therefore, the packing of the anions determines the arrangement of ions in the crystal lattice. There are several possible arrangements for ionic crystals in which the anions are larger than cations, and cations and anions are present in equal molar amounts. For example. Figure 4.22 shows two different arrangements found in the structures of sodium chloride, NaCl, and cesium chloride, CsCl. 

One problem in refining cesium is that it is usually found along with rubidium therefore, the two elements must be separated after they are extracted from their sources. The main process to produce cesium is to finely grind its ores and then heat the mix to about 600°C along with liquid sodium, which produces an alloy of Na, Cs, and Ru, which are separated by fractional distillation. Cesium can also be produced by the thermochemical reduction of a mixture of cesium chloride (CsCl) and calcium (Ca). 

Cesium chloride (CsCl) is produced by the reaction of cesium metal with chlorine gas (Ca + Cl —> CsCl). It is also used in the beer brewing industry, to coat fluorescent screens, and to improve the taste of mineral water. 

At the top right, the diagram shows the densities and sedimentation coef cients for biomolecules, cell organelles, and viruses. Proteins and protein-rich structures have densities of around 1.3 g cm , while nucleic acids show densities of up to 2 g cm . Equilibrium sedimentation of nucleic acids therefore requires high-density media—e.g., concentrated solutions of cesium chloride (CsCl). To allow comparison of S values measured in different media, they are usually corrected to values for water at 20 °C ( S20W ) ... 

Cesium, chloride (CsCl) structure (Fig. 4-H)- The CsCl structure can be described as interpenetrating simple cubic arrays of Cs+ and CP. Again, the Cs+ and CP positions are fully interchangeable. The structure is sometimes wrongly called body-centered cubic (bcc). The terminology is appropriate only when the shaded and unshaded atoms of Fig. 4.11 are identical, as in Fig. 4.8. In any case, the coordination number is eight for any atom. The unit cell of CsCl contains one net CsCl unit. 

Which would you expect to have a higher melting point sodium chloride, NaCl, or cesium chloride, CsCl Why ... 

If the substance is a binary compound AB, and if its unit cell is simple cubic P with one formula (one atom of A and one of B) per cubic cell, the relative positions of the two atoms are fixed by symmetry. This is tme of the salt cesium chloride, CsCl, the structure of which is shown in Fig. 4. One of the ions, Cs say, may without loss of generality be placed at the origin. The other ion, Cr, must be at the center of the unit cell if it is in any other position, the stracture will lack the threefold rotational axes of synunetry that are always present along all four body diagonals of the unit cell in the cubic system. 

Other AZ stmcture types include cesium chloride, CsCl (Fig. 3.11) two polymorphs of zinc sulfide-wurtzite and zinc blende and NiAs. Although these stmcture t) pes are... 

A solution is prepared by dissolving 50.0 g cesium chloride (CsCl) in 50.0 g water. The volume of the solution is 63.3 mL. Calculate the mass percent, molarity, molality, and mole fraction of the cesium chloride. 

Viscosity of aqueous cesium chloride (CsCl) solution was measured in the range of 0.1-5.0 mol kg-i and 0.1-375 MPa at 25 °C. The Jones-Dole B coefficient of CsCl was obtained from the concentration dependence of the viscosity. It is negative not only at atmospheric pressure but also at high pressure, having a maximum against pressure at about 160 MPa. Similar maximum of the B was observed for aqueous sodium chloride (NaCl) solution. The similarity is discussed in terms of the water structure and dielectric friction theory. 

Calcium fluoride (CaFg) CajF2(g) 701 Cesium chloride (CsCl) CljCs (l) 723... 

Calcium hydroxide (CaOK) CajHjOj (g) 702 Cesium chloride (CsCl) Clj CSj (cr, 1) 724... 

Calcium hydroxide (CaCOiOg) Ca H202(cr) 704 Cesium chloride (CsCl) CljCSj(g) 725... 

Calcium hydroxide (Ca(0H)2) 705 Cesium chloride ((CsCl)2) Cl2Cs2(g) 795... 

Cesium chloride (CsCl) 725 CliNaj(g) Sodiim chloride (NaCl) 773... 

Most salts crystallize as ionic solids with ions occupying the unit cell. Sodium chloride (Figure 13-28) is an example. Many other salts crystallize in the sodium chloride (face-centered cubic) arrangement. Examples are the halides of Li+, K+, and Rb+, and M2+X2 oxides and sulfides such as MgO, CaO, CaS, and MnO. Two other common ionic structures are those of cesium chloride, CsCl (simple cubic lattice), and zincblende, ZnS (face-centered cubic lattice), shown in Figure 13-29. Salts that are isomorphous with the CsCl structure include CsBr, Csl, NH4CI, TlCl, TlBr, and TIL The sulfides of Be2+, Cd2+, and Hg2+, together with CuBr, Cul, Agl, and ZnO, are isomorphous with the zincblende structure (Figure 13-29c). 

Figure 13-29 Crystal stmctures of some ionic compounds of the MX type. The gray circles represent cations. One unit cell of each stmcture is shown, (a) The stmcmre of cesium chloride, CsCl, is simple cubic. It is not body-centered, because the point at the center of the cell (Cs+, gray) is not the same as the point at a corner of the cell (Cl , green), (b) Sodium chloride, NaCl, is face-centered cubic, (c) Zincblende, ZnS, is face-centered cubic, with four Zn + (gray) and four (yellow) ions per unit cell. The...

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