Phase relations in ferroelectric/ferromagnetic TlInS2–TlCoS2 and TlGaSe2–TlCoSe2 systems

Dielectric properties of TlInS2 and TlGaSe2 as well as magnetic properties of TlCoS2 and TlCoSe2 in the temperature interval of 77–400 K have been investigated and discussed. The results show that TlInS2 and TlGaSe2 exhibited ferroelectrics behavior, meanwhile TlCoS2 and TlCoSe2 exhibited ferrimagnetic-semimetal, and ferrimagnetic-metal properties, respectively. On the base of these results the possibility of the coexistence of polar, and magnetic order in TlIn1−xCoxS2 and TlGa1−xCoxSe2 compounds has been proposed. The interaction in the quasi-binary systems TlInS2–TlCoS2 and TlGaSe2–TlCoSe2 has been studied, and the regions of homogeneous phases in these systems are revealed.