Electronic structure of the [Ni(Salen)] complex studied by core-level spectroscopies. Issue 18 (4th May 2021)

• Record Type: Journal Article
• Authors: Svirskiy, Gleb I.; Generalov, Alexander V.; Vinogradov, Nikolay A.; Brykalova, Xenia O.; Vereshchagin, Anatoly V.; Levin, Oleg V.; Lyalin, Andrey G.; Preobrajenski, Alexei B.; Vinogradov, Alexander S.
• Is Part Of: Physical chemistry chemical physics. Volume 23:Issue 18(2021)
• Page Start: 11015
• Page End: 11027
• Publication Date: 2021-05-04
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d1cp00511a
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : The energy distribution and properties of empty and occupied electronic states of [Ni(Salen)] were investigated by means of VB PES, XPS and NEXAFS spectroscopies. Abstract : The nature and structure of occupied and empty valence electronic states (molecular orbitals, MOs) of the [Ni(Salen)] molecular complex (NiO2 N2 C16 H14 ) have been studied by X-ray photoemission and absorption spectroscopy combined with density functional theory (DFT) calculations. As a result, the composition of the high-lying occupied and low-lying unoccupied electronic states has been identified. In particular, the highest occupied molecular orbital (HOMO) of the complex is found to be predominantly located on the phenyl rings of the salen ligand, while the states associated with the occupied Ni 3d-derived molecular orbitals (MOs) are at higher binding energies. The lowest unoccupied molecular orbital (LUMO) is also located on the salen ligand and is formed by the 2pπ orbitals of carbon atoms in phenyl groups of the salen macrocycle. The unoccupied MOs above the LUMO reflect σ- and π-bonding between Ni and its nearest neighbours. All valence states have highly mixed character. The specific nature of the unoccupied Ni 3d-derived σ-MO is a consequence of donor–acceptor chemical bonding in [Ni(Salen)].