The Cu2SO2 phase

The conditions of synthesis of the Cu₂SO₂ phase, its thermal characteristics and its reactivity with respect to some other phases occurring in the Cu-S-O system below 710 K, at (P_{SO_2 } ) =101 kPa, have been given. It has been established that the phase undergoes two reversible solid-state transitions, melts without decomposition at 610 K, and in the liquid state is stable up to 680 K. It is pointed out that Cu₂SO₂ is a phase thermally more stable than Cu₂SO₄.