Research Based Teaching
Recap from last week (crystal structure)
à Crystal structures, Lattice vectors, crystal basis etc.
à Reciprocal space, reciprocal lattice vectors & units, Brillouin zones à Scattering theory
Experiments
Scattering triangle Scattering probability Bragg’s law
Form factor Structure factor
à How to resolve crystal structures from scattering experiments
New Goal: Resolve crystal structure of a new 200 K superconductor!
Graphene – 2010 Nobel Prize
Usual Goal: Background preparation for the exercises
Microscopy Real space
Diffraction
Reciprocal space
H
2S under pressure - A 200 K superconductor
Powder / poly-crystal diffraction
Nature Physics 12, 835–838 (2016) 200 K superconductor
What crystal structure?
Iron under pressure
Science 330, 359 (2010)
This Week: Teaching Plan
Wednesday 07.03
Friday 09.03
Lecture 1: Summary + Form Factor Lecture 2: Structure factor
Lecture 1: Evaluation of Structure factor for SC,BCC, FCC
Lecture 2: Crystal structure determination from x-ray diffraction data
Wednesday 14.03
Lecture 1: Consolidation of new knowledge Lecture 2: Different scattering techniques
Friday 16.03: Exercise Class
Tasks for Friday
(1) Read chapter 2 :
Braggs Law
Scattering wave amplitude (read fast, don’t spend time on the derivation) Reciprocal Lattice vectors (DONE)
Diffraction conditions Laue Equations
Brillouin Zones (DONE)
Reciprocal lattice (bcc, fcc) (DONE)
Fourier Analysis of Basis (read fast, don’t spend time on the derivation) Structure factor (bcc,fcc): Read until Friday
(2) Read about: Fermi Golden rule & Fourier transforms (3) Solve next exercise sheet
(4) Optional: Install Mathematica (5) Summary:
