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The X-Ray SEF
The X-Ray SEF
This molecule is essential to life…
This molecule is essential to life…
The crystal structure of caffeine was solved using X-ray diffraction
The crystal structure of caffeine was solved using X-ray diffraction
Caffeine is a crystal because its molecule repeats in an orderly
Caffeine is a crystal because its molecule repeats in an orderly
X-Ray Diffraction is used to study crystalline materials
X-Ray Diffraction is used to study crystalline materials
The XRD pattern of every crystalline material is as distinct as your
The XRD pattern of every crystalline material is as distinct as your
Basic Diffractometer Operation
Basic Diffractometer Operation
The X-ray SEF has
The X-ray SEF has
Sample Requirements
Sample Requirements
Analyses Done Routinely in the X-ray SEF
Analyses Done Routinely in the X-ray SEF
Phase Identification and Quantification
Phase Identification and Quantification
Crystallite Size Analysis
Crystallite Size Analysis
Lattice Parameter Refinement
Lattice Parameter Refinement
in situ XRD
in situ XRD
in situ XRD of lattice parameters
in situ XRD of lattice parameters
in situ XRD of phase composition
in situ XRD of phase composition
Residual Stress Analysis
Residual Stress Analysis
Texture Pole Figures
Texture Pole Figures
Thin Film Rocking Curve
Thin Film Rocking Curve
Thin Film Reflectivity
Thin Film Reflectivity
Glancing Incident Angle Small Angle X-ray Diffraction
Glancing Incident Angle Small Angle X-ray Diffraction
Microdiffraction
Microdiffraction
Group classes are held regularly to train you to use the X-ray lab
Group classes are held regularly to train you to use the X-ray lab
Assisted Use
Assisted Use
Contact Information
Contact Information
Upcoming IAP Lectures
Upcoming IAP Lectures
Workshops for Existing X-Ray Users
Workshops for Existing X-Ray Users

Презентация: «Призма 10 класс атанасян». Автор: Scott A Speakman. Файл: «Призма 10 класс атанасян.ppt». Размер zip-архива: 2943 КБ.

Призма 10 класс атанасян

содержание презентации «Призма 10 класс атанасян.ppt»
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1 The X-Ray SEF

The X-Ray SEF

Scott Speakman 13-4009A x3-6887 speakman@mit.edu http://prism.mit.edu/xray

2 This molecule is essential to life…

This molecule is essential to life…

http://prism.mit.edu/xray

3 The crystal structure of caffeine was solved using X-ray diffraction

The crystal structure of caffeine was solved using X-ray diffraction

D. June Sutor, Acta Cryst. 11 (1958) 453

http://prism.mit.edu/xray

4 Caffeine is a crystal because its molecule repeats in an orderly

Caffeine is a crystal because its molecule repeats in an orderly

manner to fill space

http://prism.mit.edu/xray

5 X-Ray Diffraction is used to study crystalline materials

X-Ray Diffraction is used to study crystalline materials

X-rays scatter off of the atoms in a sample If those atoms are systematically ordered, the scattered X-rays tell us: what atoms are present how they are arranged

http://prism.mit.edu/xray

6 The XRD pattern of every crystalline material is as distinct as your

The XRD pattern of every crystalline material is as distinct as your

fingerprint

C8H10N4O2

C8H10N4O2?H2O

http://prism.mit.edu/xray

7 Basic Diffractometer Operation

Basic Diffractometer Operation

A detector rotates around the sample, measuring intensity as a function of the diffraction angle 2theta XRD uses information about the position, intensity, width, and shape of diffraction peaks in a pattern from a polycrystalline sample.

http://prism.mit.edu/xray

8 The X-ray SEF has

The X-ray SEF has

Rigaku High-Speed Powder Diffractometer PANalytical X’Pert Pro Multipurpose Diffractometer Bruker D8 Diffractometer with 2D Detector Bruker D8 High-Resolution Thin-Film Diffractometer PANalytical Back-Reflection Laue Single Crystal Diffractometer Bruker Apex Single Crystal Diffractometer Bruker Small Angle X-ray Scattering Instrument

http://prism.mit.edu/xray

9 Sample Requirements

Sample Requirements

The Ideal Sample

Real Samples

Sample Size Powder: 90 to 482 mm3 minimum 1.6 mm3 Solid: 10mm x 10mm min: 1mm x 1mm max: 55mm x 25mm 1” to 6” wafer Characteristics flat grain size <10 mm smooth densely packed infinitely thick (>0.3mm)

Multilayers: Co(10nm)/Fe(15nm)/MgO(2nm)/Si 42 alternating layers of GaAs(104nm) and Al0.941Ga0.059As(127nm) Powder 3 specks of blue paint 0.05mm thick coating of air-sensitive battery materials brake rotor particles in suspension

http://prism.mit.edu/xray

10 Analyses Done Routinely in the X-ray SEF

Analyses Done Routinely in the X-ray SEF

Discussed Today

Other Techniques

Index and Solve Crystal Structures Percent Crystallinity Thin Film Analysis Reciprocal Space Mapping Relaxation & Strain Defect Density Single Crystal Diffraction Crystal Orientation Twinning & Other Defects Small Angle X-ray Scattering order/disorder of polymers microstructure and porosity amorphous texture

Phase Identification Crystallite Size Estimation Lattice Parameter Refinement Residual Stress Analysis Evaluate Thin Film Quality Reflectivity for Multilayer Thin Film Analysis Small Angle Diffraction of Nano- and Meso- structures Microdiffraction Texture Analysis In-situ Diffraction

http://prism.mit.edu/xray

11 Phase Identification and Quantification

Phase Identification and Quantification

What phases, and how much of each, are present in this mixture of pigments?

21 wt% Anatase, TiO2

28 wt% Hematite, Fe2O3

51 wt% Rutile, TiO2

http://prism.mit.edu/xray

12 Crystallite Size Analysis

Crystallite Size Analysis

Rutile: XS> 100 nm

Anatase: XS= 25 nm

Hematite: XS> 100 nm

Are any of the phases nanocrystalline; if so, what is their average crystallite size?

http://prism.mit.edu/xray

13 Lattice Parameter Refinement

Lattice Parameter Refinement

La2Zr2O7 undoped

4% Y-doping

8% Y-doping

How does doping change the lattice parameter of this fuel cell electrolyte?

http://prism.mit.edu/xray

14 in situ XRD

in situ XRD

we can perform these analyses, and many more, as a function of: temperature cryostat: 11 K to RT Powder Furnace: RT to 1200 C Plate Furnace: RT to 900 C environment air vacuum inert gas mildly reactive gas time time resolution as fast as 10 sec more typical is 5+ min time resolution

http://prism.mit.edu/xray

15 in situ XRD of lattice parameters

in situ XRD of lattice parameters

How does the lattice parameter of LSO change with temperature?

c axis

b axis

a axis

angle b

http://prism.mit.edu/xray

16 in situ XRD of phase composition

in situ XRD of phase composition

How does the phase composition of this hydrogen storage material change with time at 150°C?

http://prism.mit.edu/xray

17 Residual Stress Analysis

Residual Stress Analysis

H2

Pd

Hastelloy

How do stresses in a Pd film change with H2 and temperature?

XRD at 50°C

http://prism.mit.edu/xray

18 Texture Pole Figures

Texture Pole Figures

How are the grains oriented in this refractory alloy for a satellite power system?

Rolled to 20% Reduction in Thickness (less deformed)

Rolled 95% Reduction in Thickness (more deformed)

http://prism.mit.edu/xray

Distribution of <100> and <111> directions in rolled Nb-1Zr

19 Thin Film Rocking Curve

Thin Film Rocking Curve

What is the quality of epitaxial semiconductor thin films compared to the perfect single crystal substrate?

Poor Epitaxial Thin Film

Good Epitaxial Thin Film

Perfect Single Crystal Substrate

Horrible Quality, Not Epitaxial At All, Thin Film

http://prism.mit.edu/xray

20 Thin Film Reflectivity

Thin Film Reflectivity

C

9.2

1.09

0.98

Ga2O3

1.02

0.20

2.89

GaAs

19.4

0.35

5.32

SiO2

2.1

0.71

2.76

Si

?

0.31

2.33

What is the arrangement and surface characteristics of a thin film of GaAs on a Si substrate?

Thickness (nm)

Roughness (nm)

Density (g/cm3)

http://prism.mit.edu/xray

21 Glancing Incident Angle Small Angle X-ray Diffraction

Glancing Incident Angle Small Angle X-ray Diffraction

10.056nm

Do quantum dots arrange themselves in a systematic manner with long range order? What is the average distance between the quantum dots?

http://prism.mit.edu/xray

5.901nm

5.150nm

3.924nm

Intensity (a.u.)

d-spacing (?)

q

88.27

58.85

44.14

35.31

29.43

25.22

22 Microdiffraction

Microdiffraction

How does the diffraction pattern change at different positions on a sample?

http://prism.mit.edu/xray

23 Group classes are held regularly to train you to use the X-ray lab

Group classes are held regularly to train you to use the X-ray lab

independently

Training for Self-Use Requires 1 hour X-ray Safety Course from EHS 1 hour Lab Specific Safety Training 2 hr Instrument Specific Training 2 hr Practical XRD Lecture 3 hr Data Analysis Workshop next session: late January or early February see prism.mit.edu/xray for schedule updates

http://prism.mit.edu/xray

24 Assisted Use

Assisted Use

I will gladly work with you to collect and analyze data usually needs to be scheduled ~2 weeks in advance

http://prism.mit.edu/xray

25 Contact Information

Contact Information

Scott Speakman office: 13-4009A x3-6887 speakman@mit.edu generally available 10 am to 4 pm XRD Lab: 13-4027 XRD Computer Room: 13-4041 http://prism.mit.edu/xray

26 Upcoming IAP Lectures

Upcoming IAP Lectures

Introduction to X-Ray Diffraction Jan 17, 2-5 pm, room 13-2137 Nanocrystallite Size Analysis using XRD Jan 24, 2-5 pm, room 13-2137 Thin Film Analysis using X-rays Jan 31, 2-5 pm, room 13-2137

http://prism.mit.edu/xray

27 Workshops for Existing X-Ray Users

Workshops for Existing X-Ray Users

Basic Data Analysis with Jade scheduled on request Rietveld Refinement using HighScore Plus Jan 29 and Jan 30, 1 to 5 pm room 13-4041 RSVP by Jan 25

http://prism.mit.edu/xray

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