title: Oxalate molecule as the trap for gamma-irradiation energy in the amorphous aluminosilicate Al2(OH)6H4SiO4.
abstract: Paramagnetic species which were the products of gamma irradiation at 77 K and at room temperature were studied by ESR spectroscopy in the amorphous aluminosilicate, Al2(OH)6H4SiO4, prepared in the presence and in the absence of oxalate ion. The aluminosilicate precipitated from the solution containing the oxalate ion in 10(-4) mol dm-3 concentration contained the oxalate only in trace amounts. When gamma-irradiated at 77 K and at room temperature, this compound gave the stable paramagnetic species represented by the single ESR line centered at g = 2.000. We ascribe this spectrum to the CO2- radical formed from the oxalate ion. The same aluminosilicate prepared in the absence of the oxalate either produced no stable paramagnetic product after gamma irradiation at room temperature or resulted in composite ESR spectra, indicating the presence of several paramagnetic species if irradiated at 77 K. Complex ESR spectra were transformed by heating to the stable paramagnetic centers which differed from the one obtained from oxalate ion. We conclude that in Al2(OH)6H4SiO4 oxalate acts as a trap for the gamma-radiation energy.
authors.affiliation: Ruder Bosković Institute, Zagreb, Croatia, Yugoslavia.
authors.forename: V
authors.initials: V
authors.lastname: Nothig-Laslo
authors.forename: L
authors.initials: L
authors.lastname: Horvath
authors.forename: H
authors.initials: H
authors.lastname: Bilinski
mesh_terms: D000538:Aluminum Silicates / Q000528:radiation effects*; D003037:Cobalt Radioisotopes; D004578:Electron Spin Resonance Spectroscopy; D005720:Gamma Rays; D010070:Oxalates; D019815:Oxalic Acid
chemical_list: D000538:Aluminum Silicates; D003037:Cobalt Radioisotopes; D010070:Oxalates; D019815:Oxalic Acid