Question

The unit cell with crystallographic dimensions, $a\ne b\ne c,\alpha =\gamma$ = $90$ and $\beta \ne 90$ is

• A. Triclinic
• B. Monoclinic
• C. Orthorhombic
• D. Tetragonal

Answer 1

Answer: (B)

The correct option is (b) Monoclinic

In triclinic, unit cell, dimensions are

$a\ne b\ne c,\alpha \ne \beta \ne \gamma \ne 90^{\circ }$

In orthorhombic, unit cell dimensions are

$a\ne b\ne c,\alpha =\beta =\gamma =90^{\circ }$

and in tetragonal, unit cell dimensions

$a=b\ne c,\alpha =\beta =\gamma =90^{\circ }$