what is called motif. explain motif, space lattice & hypothetical 2-dimensional crystal structure with figure.
Answers
Answer:
As we have studied in the previous topic, solids are basically of two shapes. One is an amorphous solid which has no specific shape or structure. Another is a crystalline structure or crystals which have a specific organized structure of their particles. Let us take a look.
Crystals have a structure made up of a regular arrangement of their atoms (or particles). When such an arrangement of atoms is represented in a three-dimensional structure, this is a crystal lattice. So a lattice is an array of points in a particular order which describes the arrangement of particles of a crystalline solid.
Now Auguste Bravais was French scientist who found out that there are a total of fourteen possible three-dimensional lattices. These 14 arrangements are the Bravais Lattice. They have six basic shapes. The following diagram shows you the fourteen arrangements.
Crystal Lattice and unit Cell : Bravias Lattices
Characteristics of Crystal Lattice
The fourteen Bravais Lattices show some similar characteristics. These are
Each point on the lattice represents one particle of the crystal, This is a lattice point.
This particular particle may be an atom, a molecule or even ions
These lattice points of a crystal are joined together by straight lines.
By joining of these points we get the geometry (or shape) of the crystal
Every one of the fourteen lattices has such a unique geometry
Explanation:
How many kinds of space lattices are possible in a crystal?
14
29
08
24
Ans: The correct option is “A”. There are fourteen types of lattices possible in a crystal. These are known as Bravias Lattices