The exchange interactions and the state of manganese atoms in the solid solutions in Bi3NbO7 of cubic and tetragonal modifications

Abstract

The comparative analysis of magnetic behavior of manganese-containing solid solutions Bi3Nb1 xMnxO7 δ (x¼0.01 0.10) of cubic and tetragonal modifications was performed. Based on the results of magnetic susceptibility studies paramagnetic manganese atoms in solid solutions of cubic and tetragonal modifications were found to be in the form of Mn(III), Mn(IV) monomers and exchangecoupled dimers of Mn(III)–O–Mn(III), Mn(IV)–O–Mn(IV), Mn(III)–O–Mn(IV). The exchange parameters and the distribution of monomers and dimers in solid solutions as a function of the content of paramagnetic atoms were calculated.