ABSTRACT
Here, dhkl is the spacing between the (hkl) planes that diffract the
radiation. This is the perpendicular distance between the parallel
planes and is given for the cubic crystals as:
dhkl = a√
h2 + k2 + l2 (4.12)
The XRD patterns of a powdered sample can be used to iden-
tify its crystalline phases and structural properties. An observed
shift in peak position indicates a change in d-spacing and hence
an internal strain in the crystals. An observed peak broaden-
ing is also frequently attributed to the finite size of the crystals.
The Debye-Scherrer equation relates peak width to the crystallite
size D:
