Statistical Thermodynamics with Phonons

These flashcards cover key terms and concepts related to statistical thermodynamics and phonons as discussed in the lecture.

Boltzmann distribution

A probability distribution used to describe the distribution of particles among energy states in thermal equilibrium.

Gaseous properties

Physical characteristics of gases, including pressure, volume, temperature, and amount of substance.

Imaginary harmonic modes

Vibrational modes that have negative frequencies, related to potential energy surface transitions.

Phase transitions

Changes from one state of matter to another, such as from solid to liquid.

Eyring equation

A formula used to calculate the rate of chemical reactions based on transition-state theory.

Free energy

A thermodynamic quantity equivalent to the capacity of a system to do work; related to enthalpy and entropy.

Vibrational partition function (qv)

A function that quantifies the number of energy states available to a vibrational mode at a given temperature.

Helmholtz free energy (A)

A thermodynamic potential related to the work obtainable from a closed system at constant temperature and volume.

Internal energy (U)

The total energy contained within a system, including kinetic and potential energy.

Entropy (S)

A measure of the disorder or randomness in a system; a key factor in thermodynamic processes.

Thermal expansion

The increase in volume of a substance as its temperature rises, affecting its physical properties.

Quasi-harmonic approximation

A method in solid-state physics that accounts for volume dependence of phonon frequencies, modifying harmonic behavior.

Tin monosulfide (SnS)

A compound that exhibits phase transitions at low and high temperatures, relevant for studying vibrational properties.

Lattice energy (Ulatt)

The energy required to separate one mole of a solid ionic compound into its gaseous ions.

Phase stability

The tendency of a system to remain in its current phase or to transition to another phase based on thermodynamic conditions.

Statistical thermodynamics

A branch of thermodynamics that uses statistical methods to relate the macroscopic properties of matter to its microscopic behavior.