The mechanism of electrical conductivity along polyhalide chains

✍ Scribed by Santiago Alvarez; Juan Novoa; Fernando Mota

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 396 KB
• Volume: 132
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(86)87118-4

✦ Synopsis

A theoretical study of possible mechanisms for electrical conduction along polyhalide chains [XT ] co is presented. The proposed steps are the reduction of an X,-ion to X:-; subsequent migration of a halide ion from the X:-unit to its nearest neighbor with no substantial barrier; electron transfer from an elongated X:-to its neighboring X,-; oxidation of an Xi-species to XT, and the backmigration of a halogen atom. The non-existence of a barrier for the halide ion transfer in an isolated chain can be elucidated with the help of tight-binding band calculations on the bulk and by ab initio pseudopotential calculations in the local region, where species like Xi, Xi-and X; might form as intermediates. The activation in the conduction process should therefore arise from the steps which take place at the electrodes or from interactions with the cationic sublattice in the solid.