Effect of the substitution of Mn ions bу Со ions on magnetostriction in manganites

Magnetostriction in manganites has been measured for the first time. It was found tha the substitution of Mn ions bу Со ions leads to аchange in the sign of magnetostriction and а rapid increase in its absolute magnitude. The experimental data cannot Ье described bу the curve corresponding to the single-ion mechanism.