Astronuc said:Try - Atomic Structure and Vibrational Properties of Icosahedral B4C Boron Carbide
http://people.sissa.it/~dalcorso/publications/PRL-83-3230-1999.pdf
gungunlin said:this literature doesnot give the exact positions of atoms, e.g.the coordinates of atoms in the cell. but regardless, thanks for your kind reply.
The chemical formula for boron carbide is B4C. This means that each molecule of boron carbide contains 4 atoms of boron and 1 atom of carbon.
Boron carbide is a crystalline material, meaning it has a highly ordered atomic structure. It has a rhombohedral crystal structure, with each unit cell containing 12 atoms of boron and 3 atoms of carbon.
The bond between boron and carbon in boron carbide is very strong. This is due to the high electronegativity of both elements and the covalent nature of their bond, making boron carbide one of the hardest materials known.
Boron carbide's structure has several properties that make it useful in various applications. These include its high hardness, low density, and excellent thermal stability. It also has a high strength-to-weight ratio and is resistant to chemical attack.
Boron carbide's structure is largely unaffected by changes in temperature and pressure. However, at very high temperatures, it can undergo phase transitions and may change its crystal structure. Additionally, at extremely high pressures, it can undergo amorphization, meaning it loses its crystalline structure and becomes disordered.