What is the structure of zinc blende?

What is the structure of zinc blende?

Zinc Blende is the name given to the mineral ZnS. It has a cubic close packed (face centred) array of S and the Zn(II) sit in tetrahedral (1/2 occupied) sites in the lattice, giving a Unit Cell with 8 Zn and 16 S’s. The display shows an idealised unit cell (Space group 216 F-43m).

Is zinc blende fcc or BCC?

1. Which structure does zinc blende have? In the zinc blend structure, the sulphur ions form an fcc structure and the zinc ions occupy half of the tetrahedral sites in this structure to attain charge neutrality.

What is the crystal structure of Zn?

The electronic configuration of zinc is: (Ar)(3d)10(4s)2, and it has an atomic radius of 0.138 nm. At room temperature the metal has the hexagonal close packed crystal structure. The lattice parameters are: a =0.266 nm, c = 0.495 nm.

What is the coordination number of zinc blende?

4

Statement: In ZnS (zinc blende) structure, the co-ordination number of each ion is 4.

How do you draw a zinc blende structure?

The zinc blende or ZnS crystal structure – YouTube

Where is Zn placed in ZnS structure?

In zinc blende structure (ZnS), sulphide ions are face-centred and zinc is present in alternate tetrahedral voids.

How many units is ZnS?

four
Both, zinc and sulfur have tetrahedral coordination. There are four formula units of ZnS per unit cell (S: 8 corners (8/8) + 6 faces (6/2), Zn: 4 tetrahedral holes (4/1)).

How many tetrahedral holes are in ZnS?

– Like ZnS in diamond Carbon occupies half of the tetrahedral voids or holes. – The total number of tetrahedral voids in fcc is 8. – Out of 8 voids, carbon occupies half of it means four. – Therefore the percentage of occupancy of the tetrahedral void by carbon in the diamond is 50%.

How do you find the lattice constant of zinc blende?

Calculate the zinc-blende lattice parameter (a) using the formula: a = (4/3^(1/2)) x (combined radius). For example, the lattice parameter of GaAs is: a = 0.568 nm = (4/3^(1/2)) x (0.126 nm + 0.120 nm) = (4/3^(1/2)) x (R1 + R2).

What is the formula unit of ZnS?

Both, zinc and sulfur have tetrahedral coordination. There are four formula units of ZnS per unit cell (S: 8 corners (8/8) + 6 faces (6/2), Zn: 4 tetrahedral holes (4/1)).

How many octahedral voids are occupied in ZnS?

percentage of tetrahedral voids and octahedral void remain unoccupied in zns structure are 1. 50%and 50ā„… 2.50%and100% 3.25%and 50% 4.100%and50%

Why is ZnS tetrahedral?

Summary: Zinc blend is a compound that comes in two forms: sphalerite and wurtzite. These are characterized by a 1:1 stoichiometric ratio of Zinc to Sulfur. It maintains a tetrahedral arrangement in both forms.

Introduction.

Site Zn S
Face 0 6(1/2) = 3
Corner 0 8(1/8) = 1
Total 4 4

What is the lattice parameter of zinc blende?

ZnS, Zinc Sulphide, Zinc Blend, Wurtzite
The crystal has a lattice parameter of 0.541 nm.

How many units are in ZnS?

Since the number of atoms in a single unit cell of Zn and S is the same, it is consistent with the formula ZnS. The ionic radius for Zn2+ is 74pm and for S2- is 190pm.
Introduction.

Site Zn S
Total 4 4

What is the percentage of tetrahedral holes occupied in ZnS?

you see, zinc ions occupy half of tetrahedral voids means 50% of tetrahedral voids of ZnS unit cell.

What is the band gap of ZnS?

Zinc sulfide is one of the most important II-VI compound semiconductors: it has a large (3.6 eV) direct band gap, a sizable exciton binding energy of 39 meV at room temperature1, and it may in principle support both n- and p-doping.

How do you find the lattice parameter of ZnS?

The combined radius is 0.246 nm = 0.126 nm + 0.120 nm = R1 + R2. Calculate the zinc-blende lattice parameter (a) using the formula: a = (4/3^(1/2)) x (combined radius).

How many tetrahedral voids are occupied in zinc blende?

Hence, there are a total of eight tetrahedral voids in a unit cell.

How many tetrahedral voids are in ZnS?

What is the formula of ZnS?

ZnSZinc sulfide / Formula

What type of solid is ZnS?

ZnS is a / an ionic ionic crystal.

How do you calculate tetrahedral void and octahedral?

There are two tetrahedral voids for each sphere and only one octahedral void for each sphere. Thus, in a densely packed structure of N spheres, there are: Tetrahedral voids = 2N. Octahedral voids = N.

What is the value of Z in ZnS?

āˆ“ Number of ZnS units per cell (Z) = 4.

Which type of lattice is found in ZnS?

The crystal has a lattice parameter of 0.541 nm. The crystal structure is also known as diamond cubic and may be thought of as two interpenetrating fcc lattices, one for sulphur the other for zinc, with their origins displaced by one quarter of a body diagonal.

What is the size of tetrahedral void?

Thus, the number of tetrahedral voids will be ā€œ2nā€. On the other hand, if R is the radius of the constituent spherical particle, then the radius of the tetrahedral void will be 0.225 R.

Related Post