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Structure prototypes zinc blende

The structure of Agl varies at different temperatures and pressures. The stable form of Agl below 409 K, y-Agl, has the zinc blende (cubic ZnS) structure. On the other hand, /3-AgI, with the wurtzite (hexagonal ZnS) structure, is the stable form between 409 and 419 K. Above 419 K, ft-Agl undergoes a phase change to cubic a-Agl. Under high pressure, Agl adopts the NaCl structure. Below room temperature, y-Agl obtained from precipitation from an aqueous solution exhibits prominent covalent bond character, with a low electrical conductivity of about 3.4 x 10-4 ohm 1cm 1. When the temperature is raised, it undergoes a phase change to a-Agl, and the electrical conductivity increases ten-thousandfold to 1.3 ohm-1 cm-1. Compound a-Agl is the prototype of an important class of ionic conductors with Ag+ functioning as the carrier. [Pg.383]

Among the oxides and sulphides, only CdO adopts the octahedral rock salt structure found with group 2 element, although the solid is normally very deficient in oxygen and the electrons not used in bonding give rise to metallic properties. ZnO and ZnS are prototypes of the tetrahedrally coordinated wurtzite and zinc blende (or sphalerite) structures in fact, ZnS can adopt either structure, as can CdS and CdSe. HgO and HgS have chain structures with linear two-coordination of Hg. [Pg.70]

Zinc sulfide occurs naturally as the minerals zinc blende and, more rarely, wurtzite, these are structural prototypes (see Section 5.11). It is a light-sensitive white solid and, on exposure to cathode- or X-rays, it luminesces or fluoresces and is used in fluorescent paints and radar screens. Adding Cu to ZnO results in a green phosphorescence after exposure to light, and other colour variations are achieved by using different additives. The conversion of ZnS to ZnO by roasting in air is the commercial method of producing the oxide. [Pg.640]

Zinc sulfide occurs naturally as the minerals zinc blende and, more rarely, wurtzite these are structural prototypes... [Pg.739]

As alrea mentioned, we also prepared Hg3PS4 and Hg3PS3, which have zinc blende as their prototype. An x-ray structural analysis showed that these two substances are similar in structure from this, it can be assumed that Hg3PS3 is an excess tetrahedral phase, where the cation atoms occupy all the tetrahedral vacancies. [Pg.100]

Figure 6 Prototypes of diamondlike structures (a) the cubic zinc blende (sphalaite) structure (b) the hexagonal wurtzite structure. Figure 6 Prototypes of diamondlike structures (a) the cubic zinc blende (sphalaite) structure (b) the hexagonal wurtzite structure.
Because of the importance of semiconductors in our everyday lives, it is important to draw attention to the structural similarities that exist within this group of materials. The majority of semiconductors exhibit either a diamond (Fig. 6.20) or zinc blende (Fig. 6.19) structure type, with the wurtzite structure (Fig. 6.21) being less common. In each of these prototype structures, atoms are in tetrahedral environments. Diamond-type stmetures are adopted by Si and Ge, and the addition of dopants (see Section 6.9)... [Pg.193]


See other pages where Structure prototypes zinc blende is mentioned: [Pg.99]    [Pg.153]   
See also in sourсe #XX -- [ Pg.168 , Pg.169 ]

See also in sourсe #XX -- [ Pg.191 ]




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