The correct answer is (4) A-I, B-III, C-IV, D-II.
The crystal cell types (List-I) with their corresponding angles between cell edges (List-II) once more:
(A) Cubic cell - (I) $(\alpha = \beta = \gamma = 90^\circ)$
In a cubic cell, all three angles between the cell edges are equal, and they are each 90 degrees.
(B) Monoclinic cell - (III) $(\alpha = \beta = 90^\circ, \gamma \neq 120^\circ)$
In a monoclinic cell, two of the angles between the cell edges are 90 degrees (right angles), but the third angle, $\gamma$, is not equal to 120 degrees.
(C) Triclinic cell - (IV) $(\alpha \neq \beta \neq \gamma \neq 90^\circ)$
In a triclinic cell, none of the angles between the cell edges are equal, and none of them are equal to 90 degrees.
(D) Hexagonal cell - (II) $(\alpha = \beta = 90^\circ, \gamma = 120^\circ)$
In a hexagonal cell, two of the angles between the cell edges are 90 degrees (right angles), and the third angle, $\gamma$, is equal to 120 degrees.
So, as you can see, the correct matching of List-I with List-II is as follows:
(A) Cubic cell - (I)
(B) Monoclinic cell - (III)
(C) Triclinic cell - (IV)
(D) Hexagonal cell - (II)
This matching correctly associates each crystal cell type with its corresponding set of angles between the cell edges as defined in the table you provided. |
