Numeric calculation of antiferromagnetic resonance frequencies for the   noncollinear antiferromagnet
  We present an algorithm for the numeric calculation of antiferromagnetic resonance frequencies for the non-collinear antiferromagnets of general type. This algorithm uses general exchange symmetry approach \cite{andrmar} and is applicable for description of low-energy dynamics of an arbitrary noncollinear spin structure in weak fields. Algorithm is implemented as a MatLab and C++ program codes, which are available for download. Program codes are tested against some representative analytically solvable cases. 
V.Glazkov, T.Soldatov, Yu.Krasnikova
cond-mat.str-el