Crystallography for 2nd Year Chemistry

(0001)

6F

(hk00)

<p>(h0hL)</p> Signup and view all the answers

<p>There are 7 symmetry axes in the hexagonal system.</p> Signup and view all the answers

<p>(1110)</p> Signup and view all the answers

<p>The conditions are $a_1 = a_2 = a_3 \neq c$.</p> Signup and view all the answers

<p>There are 7 mirror planes in the hexagonal system.</p> Signup and view all the answers

<p>A positive center indicates the presence of a symmetry center in the crystal structure.</p> Signup and view all the answers

<p>Symmetry elements help define the spatial arrangement of atoms in a crystal.</p> Signup and view all the answers

<p>Hexagonal bipyramid second order.</p> Signup and view all the answers

<p>Dihexagonal bipyramid.</p> Signup and view all the answers

<p>1∆c, 3a1, a2, a3.</p> Signup and view all the answers

<p>Three mirror planes (3m).</p> Signup and view all the answers

<p>a1 = a2 = a3 ≠ c.</p> Signup and view all the answers

<p>Angles α and β are both 90 degrees, while angle δ is 120 degrees.</p> Signup and view all the answers

<p>The notation (hkwL) represents a scalenohedron.</p> Signup and view all the answers

<p>A cubic system has axes of symmetry: 3a, 3b, 3c, 4 at the face diagonals, and 6 through the edges.</p> Signup and view all the answers

<p>A rhombohedron has 6 faces and is represented by the Miller index notation (h0hL).</p> Signup and view all the answers

<p>Specifying angles is crucial for understanding the geometric and symmetry properties of crystalline structures.</p> Signup and view all the answers

<p>A cube is a crystal form characterized by six equal square faces, and it has 6 faces.</p> Signup and view all the answers

<p>The Miller index notation for an octahedron is (111), and it has 8 faces.</p> Signup and view all the answers

<p>The rhombododecahedron has 12 faces and is denoted by the Miller index notation (110).</p> Signup and view all the answers

<p>A trisoctahedron has 24 faces and is represented by the Miller index notation (hhL).</p> Signup and view all the answers

<p>A positive center indicates symmetrical properties around a central point in the crystal structure.</p> Signup and view all the answers

A crystal system with a hexagonal unit cell, characterized by six-fold symmetry.

Axes, planes, and centers of symmetry within a crystal structure.

Imaginary lines within a crystal structure that define the orientation of the unit cell.

Flat surfaces defining a crystal's structure and symmetry.

Point of symmetry where opposite sides of a crystal are mirrored.

A crystal face with the Miller indices (0001).

A crystal face with Miller indices (1010).

A crystal face with Miller indices (1110).

A crystal face with Miller indices (hk00).

A crystal face with Miller indices (h0hL).

A crystal shape with two hexagonal pyramids joined at their bases, forming a double-ended pyramid.

A complex crystal shape with two hexagonal pyramids joined at their bases and further capped with 12 additional hexagonal pyramids, resulting in a highly symmetrical structure.

A crystal system characterized by a three-fold rotational symmetry axis.

The set of symmetry elements that define the trigonal system: one three-fold rotational axis (∆c), three two-fold rotational axes (a1, a2, a3), and three mirror planes (m).

The imaginary lines defining the unit cell in the trigonal system: three equal axes (a1 = a2 = a3) perpendicular to a fourth axis (c) of different length.

A crystal form with 6 faces, described by Miller indices (hkw0).

A crystal form with 6 faces, described by Miller indices (h0hL).

A crystal form with 12 faces, described by Miller indices (hkwL).

An imaginary line that defines the orientation of a cube-shaped crystal.

Flat surfaces that define the cube's structure and symmetry.

A crystal system with a cubic unit cell, characterized by three equal axes at right angles to each other.

A crystal form with six square faces, each face corresponding to the (100) crystallographic plane.

A crystal form with eight triangular faces, each face corresponding to the (111) crystallographic plane.

A crystal form with twelve rhombus-shaped faces, each face corresponding to the (110) crystallographic plane.

A crystal form with twenty-four triangular faces, each face corresponding to the (hhL) crystallographic plane, where h and L are integers.