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15/1-08 MENA3100
MENA3100
1st lecture
General information, what to learn and
some repetition of crystallography
15/1-08 MENA3100
Student contact information Name E-mail Phone
Jørn Eirik Olsen Jorneo(a)student.matnat.uio.no 41100739
Jack Bonsak Jackb(a)ulrik.uio.no 97649877
Kai K Lange Kaikl(a)student.matnat.uio.no 95141689
Joakim Aardal Joakimaa(a)student.matnat.uio.no 41479008
Magnus Kvalbein Magnuskv(a)student.matnat.uio.no 90533341
Einar Vøllestad Einarvo(a)student.matnat.uio.no 41107628
Halvard Haug Halvarha(a)gmail.com 99486757
Kristine Kostøl Kristbko(a)student.matnat.uio.no 41634468
15/1-08 MENA3100
Who is involved?
• Anette E. Gunnæs: eleonora(at)fys.uio.no, 91514080 (General, TEM, ED)
• Johan Taftø: johan.tafto(at)fys.uio.no (waves optics, TEM, EELS)
• Ole Bjørn Karlsen: obkarlsen(at)fys.uio.no (OM, XRD)
• Sissel Jørgensen: sissel.jorgensen(at)kjemi.uio.no (SEM, EDS, XPS)
• Spyros Diplas: spyros.diplas(at)smn.uio.no (XPS)
• Lasse Vines: Lasse.vines(at)fys.uio.no (SIMS)
• Terje Finnstad: terje.finnstad(at)fys.uio.no (SPM)
• Oddvar Dyrlie: oddvar.dyrlie(at)kjemi.uio.no (SPM)
• Magnus Sørby: magnus.sorby(at)IFE.no (ND)
• Geir Helgesen: geir.helgesen(at)IFE.no (ND)
15/1-08 MENA3100
General information
• Lectures– Based on “Microstructural characterization of materials” + by Brandon and
Kaplan. SPM lecture based on chapter 7.8 in second edition of “Physical methods for materials characterisation” by Flewitt and Wild. EBSD will be based on separate text.
– Some parts of the Brandon and Kaplan book will be regarded as self study material and other parts will be taken out of the curriculum (chapter 7 + some sub chapters).
• Project work– Energy related projects will be announced by the end of January– Two students will work together, rank projects with 1st-3rd priority– Written report, oral presentation and individual examination– Counts 40 % of final grade
• Laboratories– Three groups: A, B, C– Individual reports– All reports have to be evaluated and found ok before final written exam
15/1-08 MENA3100
Laboratory groups
A B C
Laboratory work will mainly take place on Tuesdays.
The trip to IFE, Kjeller has been rescheduled to Wednesday 13th of February!
15/1-08 MENA3100
What to learn about• Imaging/microscopy
– Optical– Electron
• SEM• TEM
– Scanning probe• AFM• STM
• Diffraction– X-rays– Electrons
• ED in TEM and EBSD in SEM
– Neutrons
• Spectroscopy– EDS
• X-rays
– EELS• Electrons
– XPS, AES• Electrons (surface)
– SIMS• Ions
• Sample preparation– Mechanical grinding/polishing– Chemical polishing/etching– Ion bombardment– Crunching etc……
Mapping of elements or chemical states of elements.
The same basic theory for allwaves.
Different imaging modes.
15/1-08 MENA3100
Probes used
• Visible light– Optical microscopy (OM)
• X-ray– X-ray diffraction (XD)– X-ray photo electron spectroscopy
(XPS)
• Neutron– Neutron diffraction (ND)
• Ion– Secondary ion mass spectrometry
(SIMS)– Cleaning and thinning samples
• Electron– Scanning electron microscopy
(SEM)– Transmission electron microscopy
(TEM)– Electron holography (EH)– Electron diffraction (ED)– Electron energy loss spectroscopy
(EELS)– Energy dispersive x-ray
spectroscopy (EDS)– Auger electron spectroscopy
(AES)
15/1-08 MENA3100
Basic principles, electron probeValence
K
L
M
Electronshell
Characteristic x-ray emitted or Auger electron ejected after relaxation of inner state. Low energy photons (cathodoluminescence)when relaxation of outer stat.
K
L
M
1s2
2s2
2p2
2p43s2
3p2
3p4
3d4
3d6
Auger electron or x-ray
Secondary electron
Electron
15/1-08 MENA3100
Basic principles, x-ray probe
K
L
M
Auger electron
Photo electron
X-ray Valence
K
L
M
Electronshell
Characteristic x-ray emitted or Auger electron ejected after relaxation of inner state. Low energy photons (cathodoluminescence)when relaxation of outer stat.
Secondary x-rays
15/1-08 MENA3100
Basic principles
Electrons X-rays Ions
E<Eo(EELS)
BSE
SEAE
X-rays (EDS)Ions (SIMS)
AE PE
(XD)X-rays
E=Eo
(XPS)
(Also used forcleaning/thinning samples)
SE
(SEM)
(TEM and ED)
You will learn about:- the equipment-imaging-diffraction -the probability for different events to happen-energy related effects-element related effects-etc., etc., etc……..
15/1-08 MENA3100
Basic aspects of crystallography
• Crystallography describes and characterise the structure of crystals
The unit cell !
a
c
bα
βγ
- Defined by three non planar lattice vectors: a, b and c
-The unit cell can also be described by the length of the vectors a,b and c and the angles between them (alpha, beta, gamma).
Elementary unit of volume!
15/1-08 MENA3100
Unit cell
• The crystal structure is described by specifying a repeating element and its translational periodicity
– The repeating element (usually consisting of many atoms) is replaced by a lattice point and all lattice points have the same atomic environments.
– The whole lattice can be described by repeating a unit cell in all three dimensions. The unit cells are the smallest building blocks.
– A primitive unit cell has only one lattice point in the unit cell.
a
c
bα
βγ
Replaces repeating element(molecule, base etc.)
15/1-08 MENA3100
Axial systems
The point lattices can be described by 7 axial systems (coordinate systems)
x
y
z
a
b
c
α
γ
β
Axial system Axes Angles
Triclinic a≠b≠c α≠β≠γ≠90o
Monoclinic a≠b≠c α=γ=90o ≠ β
Orthorombic a≠b≠c α= β=γ=90o
Tetragonal a=b≠c α= β=γ=90o
Cubic a=b=c α= β=γ=90o
Hexagonal a1=a2=a3≠c α= β=90o
γ=120o
Rhombohedral a=b=c α= β=γ ≠ 90o
15/1-08 MENA3100
Bravais lattice
The point lattices can be describedby 14 different Bravais lattices
Hermann and Mauguin symboler:P (primitiv)F (face centred)I (body centred) A, B, C (bace or end centred) R (rhombohedral)
15/1-08 MENA3100
Space groups
• Crystals can be classified according to 230 space groups.
• Details about crystal description can be found in International Tables for Crystallography.
– Criteria for filling Bravais point lattice with atoms.
– Both paper books and online
Figur: M.A. White: Properties of Materials
• A space group can be referred to by a number or the space group symbol (ex. Fm-3m is nr. 225)
• Structural data for known crystalline phases are available in books like “Pearson’s handbook of crystallographic data….” but also electronically in databases like “Find it”.
• Pearson symbol like cF4 indicate the axial system (cubic), centering of the lattice (face) and number of atoms in the unit cell of a phase (like Cu).
15/1-08 MENA3100
Lattice planes• Miller indexing system
– Crystals are described in the axial system of their unit cell
– Miller indices (hkl) of a plane is found from the interception of the plane with the unit cell axis (a/h, b/k, c/l).
– The reciprocal of the interceptions are rationalized if necessary to avoid fraction numbers of (h k l) and 1/∞ = 0
– Planes are often described by their normal
– (hkl) one single set of parallel planes
– {hkl} equivalent planes
Z
Y
X
(010)
(001)
(100)
Z
Y
X
(110)
(111)
Z
Y
X
y
z
x
c/l
0a/h b/k
15/1-08 MENA3100
Directions
• The indices of directions (u, v and w) can be found from the components of the vector in the axial system a, b, c.
• The indices are scaled so that all are integers and as small as possible
• Notation– [uvw] one single direction or zone axis
– <uvw> geometrical equivalent directions
• [hkl] is normal to the (hkl) plane in cubic axial systems
uaa
b
x
z
c
y
vb
wc
[uvw]
Zone axis [uvw]
(hkl)
uh+vk+wl= 0
15/1-08 MENA3100
Stereographic projection
• Plots planes and directions in a 2D map
Fig 6.5 of Klein (2002) Manual of Mineral Science, John Wiley
and Sons
All poles in a zone are on the same great circle!!
15/1-08 MENA3100
Reciprocal vectors, planar distances
• The reciprocal lattice is defined by the vectors :
• Planar distance (d-value) between planes {hkl} in a cubic crystal with lattice parameter a:
222 lkh
ad hkl
Vbac
Vacb
Vcba
/)(
/)(
/)(
*
*
*
–The normal of a plane is given by the vector:
–Planar distance between the planes {hkl} is given by:
*** clbkahg hkl
hklhkl gd /1
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