Intercalation of Methylamines into Titanium Disulfide

✍ Scribed by Lori A. Brown; William S. Glaunsinger; Michael J. McKelvy

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 149 KB
• Volume: 155
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8921

✦ Synopsis

The reactions of methylamine, dimethylamine, and trimethylamine with TiS 2 were characterized by several techniques. Detailed studies of the intercalation of methylamine demonstrated that the reaction was of the redox-rearrangement type, where the intercalate is best described as (CH 3 NH ؉ 3 ) y (CH 3 NH 2 ) y TiS 2 y؊ , with y ‫؍‬ 0.25؎0.02 and y dependent on sample history. For y ‫؍‬ 0.25 and y ‫؍‬ 0.15, this intercalate is a mixed-phase stage 1 [a ‫؍‬ 3.422(5) A s and c ‫؍‬ 28.06(10) A s ] and stage 2 [a ‫؍‬ 3.4265 A s and c ‫؍‬ 42.48(10) A s ] compound having R 3 m symmetry. Visual observation and thermogravimetric analysis of dimethylamine intercalation also suggest a redoxrearrangement mechanism. In contrast, no intercalation was observed for trimethylamine. The onset time for intercalation of liquid amines into TiS 2 at ambient temperature follows the general trend: N 2 H 4 < NH 3 < CH 3 NH 2 < (CH 3 ) 2 NH<< (CH 3 ) 3 N. This trend is consistent with an increase in steric hindrance about the N atom and decrease in the number of amine hydrogen atoms that e4ectively reduces the nucleophilic reaction rate of the intercalant.