The structure molecules can be confirmed by using X-ray diffraction analysis, which are explained by Bragg's Law. The law states that when the x-ray is incident onto a crystal surface, its angle of incidence, will reflect back with a same angle of scattering. A first-order reflection from the {111} planes of a cubic crystal was observed at a glancing angle of 18.9° when Cu(ka) X-rays of wavelength 179 pm were used. (i) Illustrate clearly the reflection of crystal using Bragg's Law. (ii) Calculate the unit cell parameters of the crystal. Calculate the angle at which the same crystal will give a reflection from the {123} planes.

The structure molecules can be confirmed by using X-ray diffraction analysis, which are explained by Bragg's Law. The law states that when the x-ray is incident onto a crystal surface, its angle of incidence, will reflect back with a same angle of scattering. A first-order reflection from the {111} planes of a cubic crystal was observed at a glancing angle of 18.9° when Cu(ka) X-rays of wavelength 179 pm were used. (i) Illustrate clearly the reflection of crystal using Bragg's Law. (ii) Calculate the unit cell parameters of the crystal. Calculate the angle at which the same crystal will give a reflection from the {123} planes.

Physical Chemistry

2nd Edition

ISBN:9781133958437

Author:Ball, David W. (david Warren), BAER, Tomas

Publisher:Ball, David W. (david Warren), BAER, Tomas

Chapter22: Surfaces

Section: Chapter Questions

Problem 22.36E

See similar textbooks

Similar questions

What is the first-order scintillation angle of the shimmering x-rays of a crystal surface with a distance between planes of 0.204 nm and a wavelength of 0.154 nm.
1) For a crystalline substance with a hexagonal unit cell, the distance interplanar d is given by the expression. Consider graphite, for which a = 0.247 nm and c = 0.679 nm. On a standardized diffractogram with Cu Kα radiation ((λ = 1.5418 Å)), where angle 2θ will be observed the Bragg 002 peak of graphite?
Explain TWO (2) effects of thermodynamic in polymerization reactions and why addition polymerizations have to be conducted at low temperature?
In an x-ray diffraction measurement of BCC Nb, the observed angle (2Θ) for the (211) set of planes occurs at 75.90 degrees (1st order) and a monochromatic x-ray source at λ = 0.1659 nm is used. Compute:a) the interplanar spacing of the (211) set of planes,b) the atomic radius of Nb,c) the anticipated 1st order observed angle (2Θ) for the (111) lattice planes in Nb.d) Estimate the relative intensities observed for the (211) and the (111) diffraction peaks in Nb. Describe your reasoning.
The surface energy of a single crystal depends on crystallographic orientation. Does this surface energy increase or decrease with an increase in planar density? Why?
The glancing angle of a Bragg reflection from a set of crystals planes separated by 128.2 pm is 19.76 0. Calculate the wavelength of the X-rays.
What is the Miller Index of the plane shown in the cubic unit cell below?
i. What is glass transition and melting temperatures Tg and Tm? Briefly describe. ii. For Polymer 2, state which one is Tg or Tm. T1: T2: iii. Compare the amount of cross-linking for Polymer 1 and Polymer 2.
A protein forms crystals of the orthorhombic type with unit-cell dimensions of 13.0 × 7.48 × 3.09 nm. If the density of the crystal is 1.315 g cm-3 and there are six protein molecules per unit cell, what is the molar mass of the protein?
State the Miller indices of the planes that intersect the crystallographic axes at the distances (2a, 3b, 2c) and (2a, 2b, ∞c).
3 Rubidium (Rb) adopts a body-centred cubic, BCC, structure at a pressure of 1 atm. Upon application of high pressure (of the order of 30,000 atm), Rb undergoes a structural phase transition to a face-centred-cubic, FCC, structure. (i) Describe what could be the main factor that induces the phase transformation. (ii) Describe how the diffraction patterns of the two forms would differ.
State the Miller indices of the planes that intersect the crystallographic axes at the distances (−a, 2b, −c) and (a, 4b, −4c).