Definitions [4]
Draw(321)
Draw (123)
Draw (102)
Explain with Diagram Hcp Unit Cell Based on Lattice Parameters.
Here, a=b≠c
And, α=β=90°, γ=120°
Every unit cell is structured as follows
In the bottom layer the central atomic surrounded by six other identical atoms.
In the middle layer at height c/2 three atoms are positioned.
In the top layer,at height C atomic distribution is similar to that of the bottom layer.
Important Questions [24]
- What Are Crystal Imperfections Mention Any Two Significance of It .
- Draw the following : (1,-1,3) ,(2,0,0) , [0,0,-1]An electron is accelerated through 1200 volts and is reflected from a crystal. The second order reflection occurs when glancing angle is 60°.
- Draw (123)
- Draw(321)
- Draw (102)
- Explain Point Defects in Crystals
- What is the principle of solar cell? Write its advantages and disadvantages
- Find the following parameter for DC(Diamond Cubic) structure:- ⦁ No. of atoms per unit cell.⦁ Co-ordination number.⦁ Nearest atomic distance.⦁ Atomic radius.⦁ APF.
- Define Ligancy. Find the Value of Critical Radius Ratio for Ligancy 3.
- Draw and explain the unit cell of sodium chloride (NaCl) crystal determine effective number of NaCl molecule per unit cell and co-ordination number.
- Calculate the critical radius ratio of an ionic crystal in ligancy-6 . what is the maximum size of cation in ligancy 6 configuration when size of anion is 2.02A°?
- Draw the unit cell of HCP structure and work out the no. of atoms per unit cell.
- Explain with Diagram Hcp Unit Cell Based on Lattice Parameters.
- A quartz crystal of thickness 1.5 mm vibrating with resonance. Calculate it’s fundamental frequency if the Young’s modulus of quartz crystal is 7.9×1010N/m2 and density is 2650 kg/m3 .
- With neat diagram of unit cell, explain the structure of NaCl crystal and calculate the no .of ions per unit cell, co ordination no. and lattice constant.
- Define Ligancy and Critical Radius Ratio. Calculate Critical Radius Ratio for Ligancy 8.
- With neat diagram of unit cell , explain the structure of HCP crystal and calculate the no. of ions per unit cell, co ordination no., lattice constant and packing factor of the structure.
- Define ligancy and critical radius ratio. Calculate critical radius radio for ligancy 6.
- A Quartz Crystal of Thickness 1 Mm is Vibrating at Resonance. Calculate Its Fundamental Frequency. (Assume that for Quartz, Y= 7.9x 1010 N/M2 and P = 2.650 Gm/Cc.
- Why X-rays Are Used to Study the Crystal Structure?
- ‘Crystal Acts as Three Dimensional Grating for X-rays’, Explain.
- Derive Bragg'S Condition for X-ray Diffraction. Monochromatic X Rays Are Incident on a Crystal. If the First Order Rejection is Observed at an Angle of 3.4•, at What Angle Would Second Order Ref
- Explain analysis of crystal structure using Bragg’s X ray spectrometer
- Explain with Example How to Determine Crystal Structure by Bragg’S X-ray Spectrometer.
Concepts [10]
- Introduction to Crystallography
- Study of characteristics of unit cell of Diamond, ZnS, NaCl and HCP;
- Miller Indices of Crystallographic Planes and Directions
- Interplanar Spacing
- X-ray Diffraction
- Bragg’S Law
- Determination of Crystal structure using Bragg’s diffractometer
- Frenkel and Schotkey Crystal Defects
- Ionic Crystal Legancy (3,4,6,8)
- Liquid Crystal Phases
