title: Picosecond Pulse Radiolysis of Highly Concentrated Carbonate Solutions.
abstract: Highly concentrated potassium carbonate aqueous solutions are studied by picosecond pulse radiolysis with the purpose of exploring the formation processes of carbonate radical CO3(•-). The transient absorption band of solvated electron produced by ionizing is markedly shifted from 715 to 600 nm when the solute concentration of K2CO3 is 5 mol L(-1). This spectral shift is even more important than that observed for the solvated electron in 10 mol L(-1) KOH solutions. The broad absorption band of solvated electron in K2CO3 solutions overlaps with that of carbonate radical CO3(•-) formed at ultrashort time. Nitrate ion is used to scavenge the solvated electron and to observe the contribution of carbonate radical CO3(•-). The analysis of the amplitude and the kinetics of carbonate radical formation in highly concentrated solutions shows that CO3(•-) is formed within the electron pulse (7 ps) by two parallel mechanisms: a direct effect on the solute and the oxidation of the solute by water radical hole H2O(•+). These two mechanisms are followed by an additional one, by reaction between the solute and OH(•) radical especially in lower concentration. The radiolytic yield of each process is discussed.
authors.affiliation: SUBATECH UMR 6457. École des Mines de Nantes, CNRS/Université de Nantes , 4, Rue Alfred Kastler, La chantrerie, BP 20722, 44307 Nantes Cedex 3, France.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ghalei
authors.affiliation: Laboratoire de Chimie Physique/ELYSE, UMR 8000 CNRS/Université Paris-Sud 11, Faculté des Sciences d'Orsay , Bât. 349, 91405 Orsay Cedex, France.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: Laboratoire de Chimie Physique/ELYSE, UMR 8000 CNRS/Université Paris-Sud 11, Faculté des Sciences d'Orsay , Bât. 349, 91405 Orsay Cedex, France.
authors.forename: Uli
authors.initials: U
authors.lastname: Schmidhammer
authors.affiliation: SUBATECH UMR 6457. École des Mines de Nantes, CNRS/Université de Nantes , 4, Rue Alfred Kastler, La chantrerie, BP 20722, 44307 Nantes Cedex 3, France.
authors.forename: Johan
authors.initials: J
authors.lastname: Vandenborre
authors.affiliation: SUBATECH UMR 6457. École des Mines de Nantes, CNRS/Université de Nantes , 4, Rue Alfred Kastler, La chantrerie, BP 20722, 44307 Nantes Cedex 3, France.
authors.forename: Massoud
authors.initials: M
authors.lastname: Fattahi
authors.affiliation: Laboratoire de Chimie Physique/ELYSE, UMR 8000 CNRS/Université Paris-Sud 11, Faculté des Sciences d'Orsay , Bât. 349, 91405 Orsay Cedex, France.
authors.forename: Mehran
authors.initials: M
authors.lastname: Mostafavi