Q3) The figure below shows an x-ray diffraction pattern for erbium nitride (ErN) taken using a diffractometer mono-chromatic x-radiation having a wavelength of 0.15418 nm; each diffraction peak on the pattern has been indexed. Assume the order of diffraction is 1. 1- Compute the interplanar spacing for only three indexed planes. 2- Determine the lattice parameter. (111) X-ray diffraction of ErN. 20 30 40 60 70 80 90 100 20 Intensity (a.u.) (00) 50 (220) -(311) -(222) (00t)

Xray light of wavelength 5.4 x 10-12m is incident on stationary electrons. Scattered light of wavelength 6.5x10-12m is detected at what scattering angle? Group of answer choices 56.9 deg 51.8 deg none of the above 24.9 deg 75 deg

Light from the He-Ne laser of wavelength 633 nm passes through a circular aperture. It is observed on a screen 2.00 m behind the aperture. The width of the central maximum is 3.40 cm what is the diameter of the hole? A. 45.4 micro meters B. 90.9 micro meters C. 3.40 centi meters D. 74.5 micro meters E. 633 nano meters

2) A thin crystal of the metal oxide with a tetragonal crystal structure and lattice parameters a = 4.05 Å and c = 2.517 Å is tilted so that a 200 kV electron beam travels along the [001] zone axis. Create a schematic diagram of zero order Laue zone (ZOLZ) diffraction pattern for a crystals of thickness: a) 75 Å b) 400 Å You should assume there are no forbidden reflections and that the diffraction intensity drops to zero when the excitation error, s, exceeds the first minimum of the relrod. You should show the approximate number of beams in the ZOLZ circle. (10)