BRAVIAS CRYSTALS -7 CRYSTAL SYSTEMS

Bravias crystals :

There are 7 different basic crystal lattices according to the dimensions (a,b,c) and their angles( ⍺, 𝛽,ℽ ) of unit cell which are called Bravias
crystals.

1 Cubic crystal system :
a=b=c and α=β=γ=90 example : NaCl
available systems are simple cubic, face centered and body centered cubic systems

2 Tetragonal
a=b ≠ c and α=β=γ=90 example SiSO4
available systems : simple and body centered cubic systems.

3 Orthorhombic
a ≠ b ≠c and α=β=γ=90 example: BaSO4
available systems are simple, body centered ,face centered and base centered cubic systems. .

4 Monoclinic (rhombohedral )
a ≠ b ≠c and α=β=90γ=120 example: Na2So4
available systems: siple and bidy centered cubic systems

5 Triclinic
a ≠ b ≠c and α≠β≠γ≠90 example: CaSo4
available systems : simple cubic system only.

6 Trigonal
a=b=c and α=β=γ≠90 example: CuSO4,

7 Hexagonal
a=b ≠ c and α=β=90γ=120, example: SiO2
available system: simple cubic crystal system .

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Meissner effect.

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PHYSICS

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