
In a hypothetical solid, C atoms are found to form cubical close-packed lattice. A atoms occupy all tetrahedral voids and B atoms occupy all octahedral voids.

A and B atoms are of appropriate size, so that there is no distortion in the CCP lattice of C atoms. Now, if a plane as shown in the following figure is cut, then the cross section of this plane will look like

A and B atoms are of appropriate size, so that there is no distortion in the CCP lattice of C atoms. Now, if a plane as shown in the following figure is cut, then the cross section of this plane will look like


Important Questions on Solid State

Consider the bcc unit cells of the solids and with the position of atoms as shown below. The radius of atom is twice that of atom The unit cell edge length is more in solid than in . What is the approximate packing efficiency in solid ?











An element crystallises in a face–centred cubic (fcc) unit cell with cell edge a. The distance between the centres of two nearest octahedral voids in the crystal lattice is:

The vacant space in bcc lattice unit cell is:





The packing efficiency of the face centered cubic (FCC), body centered cubic (BCC) and simple/primitive cubic (PC) lattices follows the order


