First-principles statistical mechanical software for the study of multi-component crystalline solids

View the Project on GitHub



CASM is an open source software package designed to perform first-principles statistical mechanical studies of multi-component crystalline solids. CASM interfaces with first-principles electronic structure codes, automates the construction and parameterization of effective Hamiltonians and subsequently builds highly optimized (kinetic) Monte Carlo codes to predict finite-temperature thermodynamic and kinetic properties. CASM uses group theoretic techniques that take full advantage of crystal symmetry in order to rigorously construct effective Hamiltonians for almost arbitrary degrees of freedom in crystalline solids. This includes cluster expansions for configurational disorder in multi-component solids and lattice-dynamical effective Hamiltonians for vibrational degrees of freedom involved in structural phase transitions.

The public version of CASM supports:


CASM is developed by the Van der Ven group, originally at the University of Michigan and currently at the University of California Santa Barbara.

The development of CASM was made possible with support from:


CASM is released under the GNU Lesser General Public License (LGPL).


Using CASM

How CASM Works

Getting Help