1. The document discusses crystalline and amorphous materials, symmetry elements in crystals like proper axes of rotation, planes of symmetry, and centers of symmetry. 2. It also discusses crystal lattices, unit cells, and calculations to determine the number of atoms in simple cubic, body centered cubic, and face centered cubic unit cells. 3. Ratios of interplanar distances are provided for different crystal structures and the structure of NaCl is described along with calculations of molecules in the unit cell. 4. Applications of solid state chemistry are mentioned including determining Avogadro's number and uses in medicine, agriculture, and domestic appliances.

1. Shri Shivaji Education Society Amravati’s
J.D.Patil Sangludkar Mahavidyalya Daryapur.
Crystalline State
By:-
Mr.Rahul G.Sawarkar
M.Sc.(Chem) SET,GATE.

2. Contents
Introduction
Symmetry Elements
Crystal Lattice
Unit Cell
Calculations of Atoms in Unit Cell
Ratio of Interplanar Distances
Structure of NaCl
Applications of Solid State in Chemistry
References

3. Introduction
Crystalline Materials
Regular Arrangements
Sharp Melting Points
Shape as well
Amorphous Materials

4. Symmetry Elements
Proper Axis of rotation Cn

5. Symmetry Elements
Plane of Symmetry σ

6. Symmetry Elements
Center of Symmetry i

7. Crystal Lattice

8. Unit Cell

9. Calculation of Atoms in Unit Cell
SCC
In SCC unit cell atoms are present at corners of the cube Therefore, one corner of Cube is
contributed in 8 Unit cells. Hence in Single unit Cell its contribution is 1/8 part of atom.
Therefore,
No.of atoms in SCC unit cell = 1/8 x No.of Corners
= 1/8 x 8
= 1

10. Calculation of Atoms in Unit Cell
BCC
In BCC unit cell atoms are present at corners and Center of the of the cube Therefore,
one corner of Cube is contributed in 8 Unit cells . Hence in Single unit Cell its
contribution is 1/8 part of atom.Atom present in center it has 100% contribution in same
cell
Therefore,
No.of atoms in BCC unit cell = 1/8 x No.of Corners +
No.of Atoms at center x 1
= 1/8 x 8 + 1
= 2

11. Calculation of Atoms in Unit Cell
FCC
In FCC unit cell atoms are present at corners and Face of the of the cube Therefore, one
corner of Cube is contributed in 8 Unit cells . Hence in Single unit Cell its contribution is
1/8 part of atom. Atom present at face contributed in two unit cell
Therefore, its contribution in one unit cell is ½.
No.of atoms in BCC unit cell = 1/8 x No.of Corners +
No.of Atoms at face x ½
= 1/8 x 8 + 6 x ½
= 4

12. Inter-planar Distance Calculation & Identification of
SCC Unit Cell

13. Ratio of Inter planer distance SCC is
d100:d110:d111 =1: 0.707:0.577
Ratio of Inter-planar distances for SCC,BCC and FCC
SCC

14. BCC
Ratio of Inter planer distance BCC is
d100:d110:d111 =1: 1.414:0.577

15. FCC
Ratio of Inter planer distance FCC is
d100:d110:d111 =1: 0.707:1.154

16. Structure of NaCl
1.NaCl is an ionic Solid made up of Na+ and Cl- ions
2. X-Ray diffraction was studied by using Bragg’s Law
3. Using First, second, third order of deflection from plane 100,
110, and 111 planes observed at angle 5.9, 8.4 and 5.20 resp.
4.Using Bragg’s equation ratio of inter planer distance calculated
is d100:d110:d111 =1: 0.707:1.154
5. This ratio of inter planer distance is allowed for FCC type
unit cell. Therefore, NaCl has FCC type unit cell
6. Each Na+ is surrounded by 6 Cl- and each Cl- is surrounded by Na+
Therefore coordination number is 6.

17. Structure of NaCl (Unit Cell)

18. Structure of NaCl

19. Calculation of NaCl Molecules in one Unit Cell
Number of NaCl molecule in 1 unit cell = No.of Na+ ions + No.of Cl- ons
Na+ ions are present at 8 corners as well as 6 faces of the cube
No.of Na+ ions = contribution by corners + Contribution by faces
= 1/8 x 8 + ½ x 6
= 1 + 3
= 4
Cl- ions are present at Center of 12 edges and at the center of the cube
No.of Cl- ions = contribution by edge + Contribution by Center
= 1/4 x 12 + 1 x 1
= 3 + 1
= 4
In one Unit Cell of NaCl has four Na+ ions and four Cl- ions
Therefore, There are 4 molecules of NaCl is present in one Unit Cell.

20. Applications
1. Avogadro's number 6.023 x 1023. This number is determined by using many more
Experiments After 18th modification in correct value of Avogadro's no. Finally Correct
and exact value of Avogadro's no is calculated by using Solid State Chemistry
2. Medical

21. Applications
3.Agriculture
Solid-State Fermentation Technology for Bioconversion of
Biomass and Agricultural Residues
4.Domestic Uses
Application Study of New Solid-State High-Power Microwave Sources
for Efficiency Improvement of Commercial Domestic Ovens