Stats Flashcards
(27 cards)
What is the canonical partition function for a degenerate and undegenerate system?
Sum of g_j exp(beta E_j) for a degenerate system with g_j= 1 for and non
Internal energy
Negative Partial differential of ln(Z) with respect to beta
Hamiltonian of two state system
Energy multiplied by the occupation numbers. These are 1 or 0 dependent on which energy state the particle is in
Microcanonical probability
One over number of micro states, number of way to distribute the wanted state among the number of particles
Entropy
Boltzmann constant multiplied by the natural log number of microstates
Heat capacity
The derivative of internal energy with respect to temperature
Helmholtz Free energy, F
Begative Boltzmann constant multiplied by temperature time natural log of the canonical partition function. U-TS
Pressure
The derivative of Gibbs free energy with respect to volume
Equilibrium temperature
One over temperature is the derivative of entropy with respect to energy
Grand canonical partition function
Q, sum over microstates the exponential of beta(muN- H) this is sum of exp( betamuN)Z
Grand canonical probability
e^(betamuN)* Z/Q
Grand potential
E-TS-muN=-kTlnQ
Entropy of grand canonical
Negative of the differential of the grand potential with respect to temperature
Number of particles in grand canonical
Negative of the derivative of the grand potential with respect to mu (chemical potential)
Grand canonical pressure
Negative of the derivative of the grand potential with respect to volume
Micro canonical
Try to start with multiplicity for probability . This is a system with no heat change or external work. N, V, E are fixed quantities
Canonical
Macrostates allow heat input but no external work. The system is maintained at a constant temperature by using a reservoir. There is a Hamiltonian for both. Try to start with partition function for probability
Canonical probability
The number of microstates of the reservoir divided by the microstates of the whole system. Becomes exponential of minus beta times Hamiltonian over Z
Difference between fermions and bosons
Bosons can have many in one state whereas for fermions there can only be 1 or 0 particles in each state
First law
dU=dQ-dW-mudN
Second law
dS=dQ/T
Gibbs free energy, G
G=U+PV-TS
What does degeneracy do to the multiplicity?
Multiple the standard form by the degeneracy of the state to the power of how many particles exist in that state
High temperature and low temperature limits quantum states
Low temp is discrete and high is continuous