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In this work, the mixed crystals, diluted magnetic semiconductors Zn0.974Mn0.026Se and Zn0.93Mn0.07Se, were studied by Raman scattering spectroscopy up to 32.4 GPa and 12.8 GPa, respectively. The high pressure was generated by using the gasketed diamond anvil cell (DAC). The semiconductor-metal phase transition pressures for these crystals occurred at 13.5 GPa and 12.8 GPa, respectively. The metallization occurred when the crystal structure transformed from a four-coordinated zinc-blende (ZB) phase into a six-coordinated rock salt (RS) phase. Before the semiconductor-metal phase transition, two new phase transitions exhibiting TO Raman mode splitting were observed at 4.5 GPa (split mode Ⅰ) and 6.3 GPa (split mode Ⅱ) for Zn0.974Mn0.026Se and at 6.2 GPa and 7.1 GPa for Zn0.93Mn0.07Se, respectively. The pressure effects on the phonon modes of LO, TO and TO split mode Ⅰ exhibited similar blue shift behavior as the Mn local phonon mode. On the contrary, the TO split mode Ⅱ exhibited red shift. The LO and Mn local mode disappeared as the pressure was higher beyond the metallization pressure, where the TO split phonon modes were still able te be observed.
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