Details

Autor(en) / Beteiligte

• Ufondu, Peter
• Boyko, Teak D
• Pointner, Monika M
• Eisenburger, Lucien
• Schnick, Wolfgang
• Moewes, Alexander

Titel

Investigating the electronic properties of novel titanium oxonitridophosphate, TiPNO, through structural distortions at the titanium sites

Ist Teil von

• Journal of materials chemistry. C, Materials for optical and electronic devices, 2024-03, Vol.12 (12), p.4392-4398

Erscheinungsjahr

2024

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Introducing new elements into binary transition metal compounds can cause crystal distortion at the transition metal site. The newly synthesized high-temperature and high-pressure titanium oxonitridophosphate Ti 5 P 12 N 24 O 2 is an example of such a compound. We analyze the structural distortion at the titanium sites by applying X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS) techniques at the Ti L 2,3 -edge. We verify the two distinct titanium sites in the lattice, each exhibiting a specific valence state. We confirm that these are both Ti 3+ and Ti 4+ with a dominant presence of the Ti 3+ cation. The degree of lattice distortion within the crystal is extracted and quantified by employing ligand field multiplet theory (LFMT) in a distorted octahedral crystal field ( D 4h ). Using the calculated distortion values, we establish a correlation between the distorted parameters (Ds, Dt) and the crystallographic bond length of Ti-N at each titanium site. There is good agreement between the calculated and measured splitting energy ( Δ e g ) of the e g orbitals and Ti 4+ is identified as the more distorted titanium site, while the Ti 3+ occupies the less distorted site in the polyhedral structure. We evaluate an electronic transition at −0.4 eV, which provides quantitative insight into the magnitude of the splitting of the e g orbital into d x 2 − y 2 and d z 2 orbitals. Through this process, we determine that Ti 3+ and Ti 4+ ions occupy sites Ti1 and Ti2, respectively.