The structural, vibrational and electronic properties of alpha-As2Te3 in different pressure environments were investigated using a diamond-anvil cell (DAC) in conjunction with AC impedance spectroscopy, Raman spectroscopy, atomic force microscopy and high-resolution transmission electron microscopy up to similar to 25 GPa. Under non-hydrostatic conditions, alpha-As2Te3 endured a structural phase transition at similar to 6 GPa, and a similar to 2 GPa delay in the transition point was observed under hydrostatic conditions. With increasing pressure, amorphization and metallization simultaneously appeared at similar to 11 GPa, as characterized by the Raman spectra and temperature-dependent conductivity results. We found that both amorphization and metallization were irreversible after decompression under non-hydrostatic conditions. However, under hydrostatic conditions, both amorphization and metallization were reversible. The unique properties displayed by alpha-As2Te3 in different pressure environments may be attributed to the effects of deviatoric stresses and the interlayer interaction constrained by the pressure medium.

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