VOID, density, packing efficiency

Packing efficiency of crystals

What will be approximate packing efficiency of the crystal which forms FCC with half the tetrahedral and octahedral voids occupied without disturbing the lattice?

Packing in ionic solid| Question based on packing efficiency

Which one of the following statements is incorrect for HCP packing arrangement in 3D? a) The coordination no.is 12 .b)It has 74% packing efficiency. c) All the octahedral void are fully present inside the unit cell. D) All the tetrahedral void are fully present inside the unit cell.

What is the packing efficiency is ccp structure?

In a close packed structure, the atoms stack together occupying maximum space and leaving minimum vacant space. The close packing arrangment may be hcp (ABABA….) or ccp (ABCABCA….). In these arrangments, there is one octahedral void and two tetrahedral voids. Depending upon the ratio of size of cation and anion, the ions of one type occupy the voids of other ions. This results in different types of crystalline structures. A metal crystallises into two cubic phases, fcc and bcc. Which phase has lesser packing efficiency and how much ?

Which of the following is correct order of packing efficiency?