The magnetic properties of layered-perovskite RbMnF4 have been investigated by neutron powder diffraction. This compound exhibits a magnetic ordering below T,=3.7&0.2 K. The resolution of the magnetic structure at 1.5 K indicates that RbMnF; orders as a collinear antiferromagnet. The propagation vector is k=O and the magnetic moment of each sublattice has a value of 2.97( 3) pfi The strong redu...

An explanation is given of the convergence behavior of IDR(s) methods. The convergence mechanism of these algorithms has two components. The first consists of damping properties of certain factors in the residual polynomials, which becomes less important for large values of s. The second component depends on the behavior of Lanczos polynomials that occur in the theoretical description. This par...