Spectroscopic approach to chlorine local environment in aluminoborosilicate glasses

• Combined XAS and XPS can investigate the chlorine local environment in glasses. • Chlorine has multiple dissolution mechanisms in glasses. • Chlorine can replace oxygen from tetrahedral units in high-pressure glasses. Chlorine local environment has been investigated using spectroscopic approach (XAS and XPS) for Na- and Ca-bearing aluminoborosilicate glasses synthesised at 1.0 GPa. Based on Cl K-edge EXAFS results, Cl appears to show two local environments in glasses: one at long distance ∼2.7 Å assigned to Cl - species charge compensated by Na + and/or Ca 2+ and one at short distance ∼1.8 Å assigned to Cl-Cl and Si-Cl species. The Cl 2p XPS results cannot unambiguously confirm the presence of Si-Cl overlapped with Na + /Ca 2+ …Cl - species.