The ratio law of the structure evolution and stability for TinOm (n = 3–18, m = 1–2n) clusters

Abstract

Most theoretical investigations about titanium oxide clusters focus on (TiO2)n. However, many TinOm clusters with ≠ 2 are produced experimentally. In this work, firstprinciples calculations are performed to probe the evolution of TinOm clusters. Our investigations show that for n=3-11, there exist one relatively stable specie; while for n=12-18, there are two relatively stable species: Ti-rich and O-rich species. HOMO-LOMO calculations show that the gap can be tuned by changing the size and configurations of TinOm clusters. Our investigation provides insights into the evolution of cluster-to-bulk process in titanium oxide.

Oxygen Deficiencies in Titanium Oxide Clusters as Models for Bulk Defects

“…Of particular note, Ti4O6 has the highest Eb of all clusters examined, aligning with its prominence in the experimental cluster distribution. Our calculated binding energies vary from previous results47 given our variation in cluster geometry. Our calculations suggest that the TinO2n-2 clusters are the most stable, yet experimentally the TinO2n-1 series is comparable in intensity.Electronic Properties.…”

“…Far less work has been performed on the suboxide clusters. 47 Our clusters show the suboxide clusters contain a similar cage structure as the stoichiometric series, except are missing either one or both terminal O. However, the formation of defect sites is accompanied by a local distortion as well as an overall compression of the cluster.…”

Communication: Effect of Oxidation on Excited State Dynamics of Neutral TinO2n-x (n<10, x<4) Clusters

“…Ti3O6 is unique among the stoichiometric clusters in that it contains a tri-coordinated Ti atom and tri-coordinated O atom, which are not present in other stoichiometric (n < 6) structures. 15,26,35 The tri-coordinated Ti atom sites are common in clusters exhibiting suppressed lifetimes. Ti3O5 exhibits a slightly longer lifetime, even though it is further undercoordinated, due to presence of partially filled d orbitals which are delocalized across two Ti atoms.…”

“…Generally, the TinO2n-1 and TinO2n clusters show longer lifetimes, and exhibit similar lifetimes due to related structures and possibly incomplete electron transfer, leading to retention of d-electrons on the stoichiometric cluster. 15 Further, in TinO2n clusters, the excited state avoids localization on the Ti atoms with terminal Ti-O bonds, 26 which ensures that the excited states behave similarly in the various O deficient clusters and accounts for the minimum influence of lifetime with oxidation. Clusters without terminal O atoms (TinO2n-2 and TinO2n-3) show shorter lifetimes and increased d-electron occupancy, indicating that the delectron scattering is a dominant mechanism affecting dynamics and that bridging O atoms have a minor effect on excited state lifetimes.…”

Photooxidation of Isoprene by Titanium Oxide Cluster Anions with Dimensions up to a Nanosize

“…Gas-phase titanium oxide clusters can be used as ideal models of the active sites on titania materials. − The structures and reactivity of small to nanosized titanium oxide clusters have been extensively studied. − The study of the interactions of titanium oxide clusters with CO under dark conditions demonstrated the outstanding reactivity of the titanium oxide clusters with specific compositions ((TiO 2 ) x O – and (TiO 2 ) x + ) that have atomic oxygen radical anions (O •– ) as the active sites. , It has been proposed that (TiO 2 ) x O – clusters with x values of up to 50 still have the O •– radicals . Although there have been many studies on the reactivity of titanium oxide clusters under dark conditions, the photoactivity of these oxide clusters has been almost untouched …”