The document is a seminar presentation on the topic of X-ray diffraction (XRD) and the rotating crystal technique. It begins with an introduction to XRD and defines it as a technique used to determine the atomic and molecular structure of crystals. It then discusses the principle behind XRD, different XRD methods including the rotating crystal technique, how to interpret XRD plots, applications of XRD, and concludes with references. The presentation contains detailed information on the fundamentals and applications of XRD using the rotating crystal method.

1. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 1
XRD-Rotating Crystal Technique
A Seminar as a part of curricular requirement for
I year M. Pharm I semester
Presented by
Udit Narayan Singh
(Reg. No. 20L81S307 )
Dept. of Pharmaceutics
Under the guidance/Mentorship of
Dr. P. Ramlingam
Professor
Dept. of Pharmaceutical Analysis

2. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 2
• Introduction
• What is XRD ?
• Principle
• Different Methods of XRD
• Rotating Crystal Method
• XRD Plot Interpretation
• Pros
• Cons
• Applications
Contents

3. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 3
Introduction
X-ray
Crystallography
X-ray
Absorption
X-ray
Fluorescence
X-ray Diffraction
Determine the arrangement of atoms within a crystal
Beam of X-rays strike a sample (Crystalline solid) and land on a detector
to produce scattered beams.

4. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 4
What is XRD ?
Crystallography
Diffraction
X - Ray
Experimental science of
determining the
arrangement of atoms in
“Crystalline solids”
Phenomenon of bending of
waves around the corners
of an obstacle
High energy
electromagnetic
radiation.
Wavelength – 10 picometer to 10 nanometer
Frequency – 30 petahertz to 30 exahertz
Energy – 124eV to 124KeV
0.2 to 10 nm is used in XRD, as it is comparable to interatomic spacing of crystalline solids

5. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 5
• XRD is based on constructive
interference of X-rays and
the crystalline sample
• Atoms in crystal refract the
X-rays which are elastically
scattered on to a detector
• This generates a 2D
diffraction pattern of the
crystal in a single orientation.
Principle

6. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 6
• Crystals are made up of
parallel planes of atoms
• Incident planes are
reflected from each plane
in a small fraction
• Constructive interference
of X-rays from successive
planes occurs when the
path difference is an
integral number of
wavelength. This is
Bragg’s Law.
Bragg’s Law
nλ = 2d Sinθ

7. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 7
Different methods of XRD
X – ray Diffraction
Orientation
Single Crystal,
Polychromatic
Beam, Fixed
angle single θ
Lattice
Parameters
Poly Crystal
Monochromatic
Beam,
Variable angle
many θ
orientation
Lattice Constant
Single Crystal
Monochromatic
Beam,
Variable angle
θ varied by
rotation
Laue
Photographic Powder
Rotating
Crystal

8. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 8
Rotating Crystal Technique

9. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 9
The Rotating Crystal Technique was developed by Schiebold in 1919.
Schematic Representation
X-ray Tube Filter
Collimating System
Crystal mounted on
a shaft
Polychromatic
X-ray
Monochromatic
X-ray
Fine beam of
parallel X-
ray

10. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 10
• Now the shaft is moved to
put the crystal into slow
rotation about a fixed axis.
• This causes the sets of planes
coming successively into their
reflecting positions.
• When the angle value
satisfies Bragg’s Equation a
spot on the photographic
plate is produced.
Schematic Diagram

11. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 11
One can take photographs in two
ways :
Complete Rotation Method –
• Occurs a series of complete
revolutions.
• Each set of planes in the crystal
diffracts four times during the
rotation.
• These four diffracted beams are
distributed into a rectangular
pattern about the central point of
the photograph.
Outline of Photograph

12. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 12
Oscillation Method –
• Crystal is oscillated through an angle of 15◦ or 20◦
• Photographic plate is also moved back and froth with a same period
• Position of a spot on the plate indicates the orientation of the crystal
Rotating Crystal Technique allows to measure the size of unit cell.
Contd.

13. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 13
• XRD pattern is a plot of the
intensity of X-rays scattered at
different angles by a sample
• The detector moves in a circle
around the sample
• The detector position is
recorded as 2θ
• The detector records number
of X-rays observed at each 2θ
• X-ray intensity is recorded as
“counts per second” or
“counts”.
XRD Plot

14. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 14
Factors for peak height –
• Periodicity in one direction
than other directions
• Preferred orientation of
crystal
• Arrangement of crystal -
Chaotic or random
• More electron density –
Increased intensity of peak
XRD Plot Interpretation
X-axis = 2θ
Y-axis = Intensity of X- ray

15. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 15
• Powerful and rapid (< 20 min) technique for identification
of an unknown sample
• In most cases, it provides an unambiguous sample
structure determination
• Minimal sample preparation is required
• XRD units are widely available
• Data interpretation is relatively straight forward
Pros

16. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 16
• Homogeneous and single phase material is best identified
• Must have access to a standard reference file of inorganic
compounds
• Requires tenths of a gram of material which must be
ground into a powder
• For unit cell determinations, indexing of patterns for non-
isometric crystal systems is complicated
• Peak overlay may occur and worsens for high angle
'reflections'
Cons

17. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 17
• Determining structure of crystals
• Polymer characterization
• Particle size determination
• Preferred orientation - Texture
• Phase identification
• Crystallite size and microstrain
• Percentage crystallinity calculation
• Miscellaneous applications
Applications

18. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 18
• A is the X-ray pattern
of one crystal
• B is the X-ray pattern
of another crystal
• C is the X-ray pattern
of excipient
• A+B+C will give a
characteristic about
the crystalline nature
of all the three.
Structure of Crystals
A
B
C
A+B+C

19. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 19
• XRD determines degree of
crystallinity in a polymer
• Non- crystalline portion
scatters x-ray beam to
give a continuous
background (amorphous
material)
• Crystalline portion causes
diffraction lines that are
not continuous (crystalline
material)
Polymer Characterization
Scatter from the instrument
Scatter from
amorphous
material
Pattern from
crystalline
material

20. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 20
Where, v = volume or size of an individual crystallite
V = total volume of specimen irradiated
n = number of spots in a diffraction ring at a Bragg angle of θ
Øθ = divergence of X-ray beam and is a function of apparatus
• Generally a series of samples having particles of known sizes is used
to obtain diffraction rings that may be compared with those from
the unknown at similar values of θ.
Particle Size Determination
v = V×θØ×cosθ / 2n

21. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 21
• Preferred orientation of crystallites can create a systematic
variation in diffraction peak intensities
Preferred Orientation (Texture)

22. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 22
• The diffraction pattern of every
phase is as unique as our
fingerprint
• Phases with same chemical
composition can have drastically
different diffraction patterns
• The position and the relative
intensity of the peaks are
compared to the reference
patterns in database to get a
knowledge of the phase volume
ratio, in this case A, B, and C.
Phase Identification
A
B
C

23. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 23
• Crystallites smaller
than 120nm create
broadening of peaks
• Microstrain may also
create peak
broadening
Analyzing the peak
widths over a long
range of 2θ will let us
separate the reason of
broadening, microstrain
or crystallite size.
Crystallite Size and Microstrain

24. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 24
• The Crystallinity of sample is calculated by separating intensities due
to amorphous and crystalline parts on diffraction.
• Percentage of Crystallinity can be calculated as ratio of Crystalline
area to total area.
Where,
Xc = % Crystallinity
Ac = Area of crystalline phase
Aa = Area of amorphous phase
Percentage Crystallinity
Xc = Ac / (Ac + Aa)

25. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 25
• Determination of Cis – Trans isomerism
• State of anneal of metals
• Soil classification based on crystallinity
• Analysis of industrial dusts
• Assessment of weathering and degradation of natural and synthetic
polymers
• Examination of factors promoting decay of tooth enamel and
dentine
• Identification of effects of disease on bone structure
• Amount of crystalline matter present in sludge, etc.
Miscellaneous

26. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 26
• Chatwal G R, Anand S K. Spectroscopy- Atomic and Molecular.
Delhi; India: Himalaya Publishing House; 2018.
• Banerjee D. X-Ray Diffraction. IIT Kanpur; India: Tata McGraw
Hills; 2017.
• Cullity B D, Stock S R. Elements of X-Ray Diffraction. Scotland;
United Kingdom: Pearson; 2015.
References

27. RIPER
AUTONOMOUS
NAAC &
NBA (UG)
SIRO- DSIR
Raghavendra Institute of Pharmaceutical Education and Research - Autonomous
K.R.Palli Cross, Chiyyedu, Anantapuramu, A. P- 515721 27
Thank You