What is structure factor?
The structure factors, F(hkl), are the fundamental quantities on which the function of electron density depends. The structure factors represent the diffracted waves, which when colliding with a photographic plate, or a detector, leave their mark in the form of well-defined spots that form the diffraction pattern.
What is structure factor of a crystal?
The crystal structure factor gives the amplitude and phase of a diffracted wave from a crystal. The factor is determined by the atom species and their positions in a unit cell.
What is the atomic packing factor of diamond structure?
The atomic packing factor of the diamond cubic structure (the proportion of space that would be filled by spheres that are centered on the vertices of the structure and are as large as possible without overlapping) is π√316 ≈ 0.34, significantly smaller (indicating a less dense structure) than the packing factors for …
How do you find the structure factor?
Definition
- The structure factor \mathbf{F}_{hkl} is a mathematical function describing the amplitude and phase of a wave diffracted from crystal lattice planes characterised by Miller indices h, k, l.
- \mathbf{F}_{hkl} = F_{hkl}\exp(i\alpha_{hkl}) = \sum_j f_j\exp[2\pi i (hx_j + ky_j + lz_j)]
What is diamond crystal structure?
The crystal structure of a diamond is a face-centered cubic or FCC lattice. Each carbon atom joins four other carbon atoms in regular tetrahedrons (triangular prisms).
Why is structure factor important?
The structure factor plays a very important role in the determination of the crystal structure because it is the only factor that gives us information about the atomic positions. The main problem in a structure analysis is just the inability to fully determine in an X-ray diffraction experiment the structure factor.
Why is diamond APF so low?
atomic packing factor (or) packing density is 0.34. It is the lowest packing density material because in diamond, carbon atoms have low mass number, and hence a smaller radius. small atoms cannot be packed closely.
Does diamond have a tetrahedral structure?
In a diamond, the carbon atoms are arranged tetrahedrally. Each carbon atom is attached to four other carbon atoms 1.544 x 10-10 meter away with a C-C-C bond angle of 109.5 degrees. Because of its tetrahedral structure, diamond also shows a great resistance to compression.
What is structure factor for simple cubic crystal?
No matter what atom coordinates or plane indices you substitute into the structure factor equation for simple cubic crystals, the solution is always non-zero. Thus, all reflections are allowed for simple cubic (primitive) structures. – 0,0,0; – ½, ½, ½. = non-zero → reflection.
What is the structure of diamond called?
Why diamond is not Bravais lattice?
The four nearest neighbors of each point form the vertices of a regular tetrahedron. The diamond lattice is not a Bravais lattice, because the environment of each point differs in orientation from the environment of its nearest neighbors. The 4×4 cell of the diamond lattice is shown in Fig. 2.