title: Hydration structure of the Ti(III) cation as revealed by pulse EPR and DFT studies: new insights into a textbook case.
abstract: The (17)O and (1)H hyperfine interactions of water ligands in the Ti(III) aquo complex in a frozen solution were determined using Hyperfine Sublevel Correlation (HYSCORE) and Pulse Electron Nuclear Double Resonance (ENDOR) spectroscopies at 9.5 GHz. The isotropic hyperfine interaction (hfi) constant of the water ligand (17)O was found to be about 7.5 MHz. (1)H Single Matched Resonance Transfer (SMART) HYSCORE spectra allowed resolution of the hfi interactions of the two inequivalent water ligand protons and the relative orientations of their hfi tensors. The magnetic and geometrical parameters extracted from the experiments were compared with the results of DFT computations for different geometrical arrangements of the water ligands around the cation. The theoretical observable properties (g tensor (1)H and (17)O hfi tensors and their orientations) of the [Ti(H(2)O)(6)](3+) complex are in quantitative agreement with the experiments for two slightly different geometrical arrangements associated with D(3d) and C(i) symmetries.
authors.affiliation: Dipartimento di Chimica IFM, Università di Torino and NIS, Nanostructured Interfaces and Surfaces Centre of Excellence, Via P. Giuria 7, I-10125 Torino, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Maurelli
authors.forename: Stefano
authors.initials: S
authors.lastname: Livraghi
authors.forename: Mario
authors.initials: M
authors.lastname: Chiesa
authors.forename: Elio
authors.initials: E
authors.lastname: Giamello
authors.forename: Sabine
authors.initials: S
authors.lastname: Van Doorslaer
authors.forename: Cristiana
authors.initials: C
authors.lastname: Di Valentin
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Pacchioni
mesh_terms: D002412:Cations / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D008024:Ligands; D015394:Molecular Structure; D011789:Quantum Theory; D012996:Solutions; D014025:Titanium / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D002412:Cations; D008024:Ligands; D012996:Solutions; D014867:Water; D014025:Titanium