How to Calculate Planar Density

••• Jupiterimages/Pixland/Getty Images

Atoms can be packed together densely or loosely. In crystalline materials such as metals, atoms are packed on periodic, three-dimensional arrays. In non-crystalline materials such as silicon oxide, atoms are not subject to periodic packing. The basic component of a crystal structure is a unit cell. Planar density is a measure of packing density in crystals. The planar density of a face centered cubic unit cell can be calculated with a few simple steps.

    Calculate the number of atoms centered on a given plane. As an example, there are 2 atoms on a (1 1 0) plane of an FCC crystal.

    Find the area of the plane. As an example, the area of a (1 1 0) plane of an FCC crystal is 8_sqrt(2)_R^2 where "R" is the radius of an atom within the plane.

    Calculate planar density with the formula:

    PD = Number of atoms centered on a given plane / Area of the plane.

    Substitute the value calculated in step 1 for the numerator and the value calculated in step 2 for the denominator.

Related Articles

How to Calculate the Packing Fraction of a Diamond...
How to Find Lattice Constant
How to Calculate the Volume of an Atom
How to Determine the Lattice Parameter of Zinc-Blende
What Are Representative Particles of Elements?
Types of Bonding in Crystals
How Does Temp Affect the Growth Rate of Crystals?
Density & Temperature of the Lithosphere
How to Calculate Interplanar Spacing
How to Find the Volume of Cube Stacking
How to Calculate Particle Concentration
What Is the Effect of Atomic Radius on the Chemical...
How to Calculate the Force of an Electromagnet
How to Calculate Bond Angles
How to Determine the Positive & Negative Sides of a...
How to Calculate Volume of a Rectangular Prism
Number of Protons in an Uncharged Atom
How to Find the Number of Ions in a Compound
Why Is the Periodic Table Arranged in Columns & Rows?
How to Find the Neutrons in the Periodic Table