What is the minumum acceleration potential (V) that must be applied to a beam of free electrons for diffraction to occur in a crystal of niobium (Nb)? Express your answer in volts.

Answer 1

Any ideas?

Answer 2

2.6 *10^3 Volts

Answer 3

2.7*10^3, sorry

Answer 4

Dude its wrong again

Answer 5

Nb is BCC and if you solve it, it gives you 2667 Volts but when you put it as your answer it gives X mark :(

Answer 6

My solution
if BCC first plane to give maximum wavelenth is (110) plane.

Then use lambda = 2dsin(theta) but since you want to maximize the lamdba assume that (theta) = 90 degrees

So lambda = 2d only

d = a(lattice constant) / sqrt (h^2 + k+2 + l^2)

solve for a, plug in (110) for (hkl)

then use lambda = hc/eV

to solve for Volts

Answer 7

Has anyone the right answer?