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Ti12C68: A stable T h -symmetry hollow cage.

ABSTRACT: A stable T h -symmetry Ti12C68 cage was systemically investigated using density functional theory. The structure of Ti12C68 is a hollow cage with twelve TiC13 subunit of three pentagons and one hexagon. The calculated frequencies are in the range 95.1 cm-1-1423.9 cm-1. There are no imaginary frequencies, showing its kinetic stability. Ab initio molecular dynamics simulations demonstrate that the topological structure of cage-like Ti12C68 cluster was well maintained when the effective temperature is up to 1139 K. The natural bond orbitals analysis shows that the d orbit of Ti atoms form four ? bonds with the neighboring four carbon atoms in each TiC13 subunit playing an important role in the cluster stability. The molecular frontier orbitals analysis indicates that Ti12C68 cage has a narrow HOMO-LUMO gap with metal-like property. It would be expected to enrich the species of hollow metal carbide clusters.

SUBMITTER: Ai LY

PROVIDER: S-EPMC5843587 | biostudies-other | 2018 Mar

REPOSITORIES: biostudies-other

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Ti12C68: A stable T h -symmetry hollow cage.

Ai Ling-Yan LY Zhao Hui-Yan HY Ma Hong-Man HM Wang Jing J Liu Ying Y

Scientific reports 20180308 1

A stable T h -symmetry Ti12C68 cage was systemically investigated using density functional theory. The structure of Ti12C68 is a hollow cage with twelve TiC13 subunit of three pentagons and one hexagon. The calculated frequencies are in the range 95.1 cm-1-1423.9 cm-1. There are no imaginary frequencies, showing its kinetic stability. Ab initio molecular dynamics simulations demonstrate that the topological s ...[more]

PMID: 29520030

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