The Weiss symbol of a crystal face is 4a: 2b: c. The value of h in the...
The Weiss parameters, introduced by Christian Samuel Weiss in 1817, are the ancestors of the Miller indices. They give an approximate indication of a face orientation with respect to the crystallographic axes, and were used as a symbol for the face.
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The Weiss symbol of a crystal face is 4a: 2b: c. The value of h in the...
Explanation:
The Weiss symbol of a crystal face is given as 4a: 2b: c.
This means that the crystal face intercepts the crystallographic axes in the ratio of 4 : 2 : 1.
The Miller indices (hkl) of a crystal face are determined by multiplying the intercepts of the face on the crystallographic axes by the reciprocal of the lattice parameters (a, b, c).
Therefore, the Miller indices of the crystal face can be calculated as follows:
h : k : l = (4/a) : (2/b) : (1/c)
To determine the value of h in the Miller indices, we need to isolate h in the above equation.
Multiplying both sides by a/c, we get:
h(a/c) : k(2/b) : l = 4 : 2 : 1
hence, h(a/c) = 4, which gives h = 4c/a.
Since the value of h must be an integer, we can choose a and c such that h takes the value of 1.
Therefore, the value of h in the Miller indices (hkl) for the given Weiss symbol is 1.
The Weiss symbol of a crystal face is 4a: 2b: c. The value of h in the...