Welcome to 3 · Lecture #18, X-Ray Diffraction Techniques Author: Prof. Donald Sadoway Created...

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Welcome to 3.091 Lecture 18

October 21, 2009

X-Ray Diffraction Techniques

ν = R

staircase

Moseley's Law

2( (1 1 Z-γ n2f n2

i ( (

Bremsstrahlung

Figure 12.14a

O

P

P'

P''

d

d

O'

A(hkl)

(hkl)

(hkl)

B D d

C

α

α

Image by MIT OpenCourseWare.

Averill, B., and P. Eldredge. Chemistry: Principles, Patterns, and Applications. Flat World Knowledge, 2011. ISBN: 9781453331224.

a a

2 a 2

h+k+l even

h+k+lall all even

or all odd unmixed

Figure 12.13

diffractometry

Figure 12.13

� = 0.1542 nm (Cu K�-radiation)

0

20

40

60

80

100

Inte

nsity

(arb

itrar

y un

its)

(111)

(200)

(220) (311)

(222) (400) (331) (420)

20 30 40 50 60 70 80 90 100 110 120

2α (degrees)

Image by MIT OpenCourseWare.

Figure 12.13

Image by MIT OpenCourseWare.

(111) Averill, B., and P. Eldredge. Chemistry: Principles, Patterns, and Applications. Flat World Knowledge, 2011. ISBN: 9781453331224.

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

120° rotation

All M. C. Escher works © 2010. The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010 The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

4-fold

90o

4-fold

90o

3-fold

120o

4-fold

90o

3-fold

120o

2-fold

180o

All M. C. Escher works © 2010 The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

All M. C. Escher works © 2010 The M. C. Escher Company – The Netherlands. All rights reserved. www.mcescher.com

translational symmetry without rotational symmetry

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Ron Lifshitz. Used with permission.

rotational symmetry without translational symmetry

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Ron Lifshitz. Used with permission.

not a Bravais lattice

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Ron Lifshitz. Used with permission.

5-fold

72o

Courtesy of Ron Lifshitz. Used with permission.

Courtesy of Dan Shechtman. Used with permission.

Courtesy of Dan Shechtman. Used with permission.

5-fold

72o

“Mission Impossible” – an example of 5:4 time Courtesy of Ron Lifshitz. Used with permission.

MIT OpenCourseWare http://ocw.mit.edu

3.091SC Introduction to Solid State Chemistry Fall 2009

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