What is a close-packed hexagonal structure?

What is a close-packed hexagonal structure is introduced as follows:

Close-packed hexagonal structures are usually used in the study of solid substances, including crystalline and amorphous substances. Molecules of substances with this structure will be arranged in the following form: each layer will have three densely packed atomic layers, and * * * will have six atomic layers, forming a cycle.

1. Introduction

Close-packed hexagonal structure is a unique arrangement in solid matter and one of the more common structural types. It consists of a pile of hexagonal cells, and the atoms in the cells are closely arranged into hexagonal stars in the crystal.

2. Ordinary close-packed hexagonal structure

Metals such as iron, cobalt, nickel and steel. Usually has a dense hexagonal structure. In addition, inorganic substances such as zinc ore and rhodochrosite also have a close-packed hexagonal structure.

3. Characteristics of close-packed hexagonal structure

Close-packed hexagonal structure has a high degree of symmetry, and its limitation is that the radii of different atoms must be equal. In this structure, the number of atoms around each atom is the same, which leads to its appearance in many important materials.

4. Application of close-packed hexagonal structure

Close-packed hexagonal structures are widely used in engineering fields, especially in material science and structural engineering, because of their high symmetry. For example, steel products, electronic equipment and aero-engines are all manufactured based on close-packed hexagonal structures.

The above is the related content of close-packed hexagonal structure, which is widely used in many fields and is very important for material science and structural engineering.

Features:

The close-packed hexagonal structure is characterized in that the adjacent atoms on the intracellular (000 1) plane are all tangent, and the nearest adjacent atoms on the two adjacent (000 1) planes are also tangent. Atom A is tangent to six atoms B, C, D, E, F and G in the same layer (000 1), and tangent to atoms H, J and K in the lower layer. Obviously, atom A is also tangent to three atoms in the upper layer (not shown in the figure).

Thus, each atom has 12 nearest neighbors in the close-packed hexagonal structure, that is, the coordination number is 12. From the simple geometric relationship, it is proved that only when C/A = (8/3)1/2 =1.633 can the above close packing condition be satisfied.