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Stability of hypothetical Ag^IICl₂ polymorphs under high pressure, revisited: a computational study.

ABSTRACT: A comparative computational study of stability of candidate structures for an as-yet unknown silver dichloride AgCl₂ is presented. It is found that all considered candidates have a negative enthalpy of formation, but are unstable towards charge transfer and decomposition into silver(I) chloride and chlorine within the DFT and hybrid-DFT approaches in the entire studied pressure range. Within SCAN approach, several of the "true" Ag^IICl₂ polymorphs (i.e. containing Ag(II) species) exhibit a region of stability below ca. 20 GPa. However, their stability with respect to aforementioned decomposition decreases with pressure by account of all three DFT methods, which suggests a limited possibility of high-pressure synthesis of AgCl₂. Some common patterns in pressure-induced structural transitions observed in the studied systems also emerge, which further testify to an instability of hypothetical AgCl₂ towards charge transfer and phase separation.

SUBMITTER: Grzelak A

PROVIDER: S-EPMC8782826 | biostudies-literature |

REPOSITORIES: biostudies-literature

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