1. At the interface of anether/aqueous solution, colloidal CdS nanocrystals (assume theseare spherical) self-assemble into a close-packed body-centeredcubic (BCC) superlattice:
a) What is a colloid?
b) Draw a unit cell of the BCC superlattice
c) Calculate the packing efficiency of the BCC lattice - howdoes this compare with a FCC lattice - explain why it issmaller/larger
d) If the length of the unit cell is 34nm, determine the radius ofthe nanoparticles.