Evolution of chemical bonding and electron density rearrangements during D3h → D3d reaction in monolayered TiS2: A QTAIM and ELF study

• Published in: Journal of computational chemistry Vol. 35; no. 22; pp. 1641 - 1645
• Main Authors: Ryzhikov, Maxim R., Slepkov, Vladimir A., Kozlova, Svetlana G., Gabuda, Svyatoslav P.
• Format: Journal Article
• Language: English
• Published: Blackwell Publishing Ltd 15.08.2014
• Subjects: DFT; electron localization function; monolayered titanium disulfide; quantum theory of atoms in molecules; solid-state reaction
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.23662

Monolayered titanium disulfide TiS2, a prospective nanoelectronic material, was previously shown to be subject to an exothermic solid‐state D3h–D3d reaction that proceeds via a newly discovered transition state. Here, we study the reaction in detail using topological methods of quantum chemistry (quantum theory of atoms in molecules and electron localization function analysis) and show how electron density and chemical bonding between the atoms change in the course of the reaction. The reaction is shown to undergo a series of topological catastrophes, associated with elementary chemical events such as break and formation of bonds (including the unexpected formation of SS bonding between sulfur layers), and rearrangement of electron density of outer valence and core shells. © 2014 Wiley Periodicals, Inc. A solid‐state D3h → D3d reaction in monolayered TiS2 is studied with topological methods of quantum chemistry. A weak exchange interaction between sulfur layers in H‐TiS2 and TS‐TiS2 states is discovered. The interaction indicates a reduction reaction accompanied by formation of a mixed Ti4+(d0)–Ti2+(d2) valence oxidation state along with S22− anions. The result can be an important factor for understanding the nature of stabilization of MX2 transition metal structures.