###### SAED d value and XRD Peak Position calculator

**Calculation Tutorial:**

**STEP1:**Take the raw image of Selected Area Electron Diffraction (SAED) from Transmission Electron Microscope (TEM)

**STEP2:**Now enter the distance (nm) between two bright spots into "Distance between 2 bright spots" column of the calculator. You should get the calculated result of d value in the field below.

**SAED d value calculation**

**NOTE:**XRD peak position is calculated by taking Laser wavelength as 0.15418 and n value as 1. The distance is in reciprocal space. We have made the calculator such that if you measure the distance directly from 1/nm scale (as shown in image) it would give you the exact d value results.

**Theory behind d value calculation:**Selected Area Electron Diffraction (SAED) is very important technique to determine the crystal structure of any material. It is a complementary technique in Transmission Electron Microscope (TEM), in which the Electrons are diffracted at a selected area and bright spots with dark background are observed as a result of this.

Distance between two bright spots (D) = 2 × Radius of that circle

The distance is in reciprocal space so we take inverse to convert it into real space

Thus, the formula for Interplanar spacing (d):

Interplanar spacing (d) = 2 / Distance between two bright spots