Modelling Carbon for Industry: Radiolytic Oxidation

✍ Scribed by P. Leary; C.P. Ewels; M.I. Heggie; R. Jones; P.R. Briddon

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 302 KB
• Volume: 217
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/(sici)1521-3951(200001)217:1<429::aid-pssb429>3.0.co;2-j

✦ Synopsis

An ab initio density functional technique (AIMPRO) has been employed to investigate the structure, vibrational properties, and dissociation mechanisms of CO 0 3 , the important radical anion CO À 3 and the interaction of this species with the graphite basal plane. The results are discussed in the context of the radiolytic oxidation of graphite: a process of relevance to the British nuclear industry, which relies for the most part on graphite-cored, CO 2 -cooled reactors. The radiation field splits coolant molecules and produces, amongst other things, a very reactive radical anion CO À 3 , which has been suggested as the main agent for the accelerated oxidation of graphite. This paper shows that CO À 3 binds strongly to graphite after combining with an electronic hole and forming a long and strong ionic bond. It still remains mobile on the basal plane and can diffuse to a graphite edge and oxidize it.