Structure Analysis of Tantalum Chloride–Graphite Intercalation Compound Using Molecular Simulations

✍ Scribed by Pavla Čapková; Jürgen Walter

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 457 KB
• Volume: 149
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1999.8497

✦ Synopsis

Structure analysis of graphite intercalated with TaCl ؊ 6 and TaOCl 3 has been carried out using molecular mechanics simulations and compared to previously published experimental data obtained by X-ray powder di4raction, electron di4raction, and other techniques. The basal spacing calculated for the second stage of graphite intercalated with tantalum(V) chloride c 2 (calc) ‫؍‬ 12.80 A s was in agreement with the experimental value c 2 (exp) ‫؍‬ 12.79 A s obtained from X-ray powder di4raction. Modeling revealed the two-dimensional ordering of TaCl ؊ 6 octahedra in the interlayer space of graphite lattice. This ordered interlayer structure of TaCl ؊ 6 is incommensurate with the graphite lattice and can be described as the two-dimensional space group 17pm6, hexagonal plane lattice with the lattice parameter 6.54 A s . The simulated electron di4raction pattern for calculated structure was in good agreement with that seen in the experiment. The guest layer lattice parameter obtained from electron di4raction was 6.5 A s . The simulations gave evidence that this guest structure can be obtained only with TaCl ؊ 6 octahedra as guests; other possible guests=TaCl 5 dimers=can be de5nitely excluded. In case of tantalum oxychloride the fragments of TaOCl 3 chain structure are arranged in the interlayer space, giving the basal spacing of the second stage c 2 (calc) ‫؍‬ 13.39 A s .