  Unlike ferromagnetism, antiferromagnetism cannot readily be included in the
quasiclassical Keldysh theory because of the rapid spatial variation in the
directions of the magnetic moments. The quasiclassical framework is useful
because it separates the quantum effects occurring at length scales comparable
to the Fermi wavelength from other length scales, and has successfully been
used to study a wide range of phenomena involving both superconductivity and
ferromagnetism. Starting from a tight-binding Hamiltonian, we develop general
quasiclassical equations of motion and boundary conditions, which can be used
to describe two-sublattice metallic antiferromagnets in the dirty limit. The
boundary conditions are applicable also for spin-active boundaries that can be
either compensated or uncompensated. Additionally, we show how nonuniform or
dynamic magnetic textures influence the equations and we derive a general
expression for observables within this framework.
