Question

The interracial angles of a triclinic crystal system are given by __________

(a) α = β = ϒ = 90o

(b) α = β = 90o ϒ = 120o

(c) α = β = ϒ ≠ 90o

(d) α ≠ β ≠ ϒ ≠ 90o

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This key question is from Types of Solids, Crystal Structures and Lattices topic in chapter Solid Solutions & Crystallography of Engineering Material & Metallurgy

Answer 1

Right answer is (d) α ≠ β ≠ ϒ ≠ 90o

Easiest explanation: The crystal system is a system by which crystal structures are classified.  Each crystal system is defined by the relationship between edge lengths a, b, and c and interaxial angles α, β, and ϒ. For the triclinic system, the interaxial angles are given by α ≠ β ≠ ϒ ≠ 90o.