The tag has no wiki summary.

learn more… | top users | synonyms

0
votes
2answers
90 views

Compute distance between planes in a crystal

I want to compute the distance between two (111) planes in a cubic crystalline structure, in order to do some computations involving Bragg reflection. I have a sketch of which the (111) planes are, ...
2
votes
1answer
23 views

How many atoms does one need to get reliable crystal information with X ray or electron diffraction?

I know that, in theoretical derivations of X ray diffraction (XRD) or electron diffraction (ED), we always assume an infinite lattice, and, as you make the crystal smaller, edge effects start to ...
1
vote
0answers
46 views

Why does inelastic X-ray scattering probe the longitudinal dielectric function as opposed to the transverse dielectric function?

Light is a transverse wave. Therefore, light in the optical range (i.e. visible light) couples to transverse collective excitations of a material when measuring the optical conductivity for instance. ...
1
vote
0answers
62 views

Pseudocubic unit cells: how to construct one?

I keep coming across the term pseudocubic unit cell while reading about orthorhombic perovskite structures. No clear explanation ...
0
votes
0answers
15 views

Impurities involved in nucleation centres

When magmas begin to crystallise, a first step is the formation of a crystal nucleus around an impurity (nucleation centre), whereby a few of the right atoms get together to form a speck of a crystal. ...
0
votes
0answers
52 views

Bragg's law - intensity “sensitivity” to lattice spacing or scattering angle

I don't understand this sentence (emphasis added): A consideration of Bragg's law (nλ = 2dsinθ), i.e. the relationship between scattering angle (θ) and the interplanar spacing (d) shows that if ...
0
votes
0answers
56 views

Electron scattering

I'm trying to figure out the missing step here, in a problem about X-ray crystallography. I am referring to the attached image: In the image, $A =$ electron density, $Z =$ distance traveled, ...
0
votes
0answers
32 views

When does a crystal take the shape of its Primitive Cell?

I know thought that a crystal, if annealed for long enough at high enough temperatures, will "shed" its higher index (higher energy) planes, leaving only its most stable form. This, I wrongfully ...
0
votes
0answers
2k views

How to calculate lattice parameter of wurtzite struture

I am trying to calculate lattice parameter of ZnO (wurtzite). I have found out the formula for calculating lattice parameter of this system from a research article. $\frac{1}{^{d^{2}}}=\frac{H ^{2}+ ...