Crystalline Structures and Phase Transitions

A set of flashcards covering key vocabulary related to crystalline structures, phase transitions, and nano-material properties.

(111) planes

These planes in a cubic structure have a smaller d-spacing compared to other planes like (001).

NaCl structure

In this structure, each Na ion is surrounded by 6 Cl ions, not 4.

octahedral geometry

Refers to a structure where each atom is surrounded by six others in an octahedral arrangement.

lattice sites

These points in a crystalline structure are geometrically identical with the same surrounding.

tetrahedral sites

In a close-packed structure, there are 8 tetrahedral sites for every octahedral site.

cubic site

A type of site in crystal structures that is larger than an octahedral site when generated by the same atoms.

BCC structure

This structure is not produced by stacking dense atomic layers in the ABC sequence.

XRD

X-ray diffraction, a technique used to analyze crystal structures, but not for measuring atomic orbital energy.

Miller Indices

A notation system in crystallography to denote the orientation of planes in a crystal lattice.

gold and silver nanoparticles

These nanoparticles influence the color variations in stained-glass due to their light-scattering and plasmonic properties.

Zeolite crystals

These materials are known for their efficiency as catalysts.

d-spacing

The distance between planes in a crystal lattice, which can be calculated using Bragg's Law.

ternary compound

A compound composed of three different elements or components.

cooling rate

The rate at which temperature falls; affects the crystallization process and the formation of structures like glass.

Density of states

The number of available electronic states per unit energy at a given energy level.

supercooled liquid

A liquid that remains in a liquid state below its freezing point without crystallizing.

viscosity

A measure of a fluid's resistance to deformation, crucial in describing the behavior of melts.

Gibbs free energy (ΔG)

A thermodynamic potential that helps predict the spontaneity of processes during phase transitions.

relaxation time (τ)

The time it takes for the molecular arrangement in a material to return to equilibrium after a disturbance.

Vapor-Liquid-Solid (VLS) method

A technique for nanowire synthesis involving the catalytic growth of nanowires from a liquid droplet.

Brillouin zone

The fundamental region in reciprocal space that contains all unique electron wavevectors.