Delocalization tunable by ligand substitution in [L2Al]n− complexes highlights a mechanism for strong electronic coupling

Autor:	Amanda M. Bohanon, Allison M. Smith, Louise A. Berben, James C. Fettinger, Tobias J. Sherbow, R. David Britt, Richard I. Sayler, Amela Arnold
Rok vydání:	2021
Předmět:	Valence (chemistry) 010405 organic chemistry Chemistry General Chemistry Class iii Electron Intervalence charge transfer 010402 general chemistry Alkali metal 01 natural sciences 0104 chemical sciences Metal Delocalized electron Crystallography visual_art Polar effect visual_art.visual_art_medium
Zdroj:	Chemical Science. 12:675-682
ISSN:	2041-6539 2041-6520
DOI:	10.1039/d0sc02812f
Popis:	Ligand-based mixed valent (MV) complexes of Al(iii) incorporating electron donating (ED) and electron withdrawing (EW) substituents on bis(imino)pyridine ligands (I2P) have been prepared. The MV states containing EW groups are both assigned as Class II/III, and those with ED functional groups are Class III and Class II/III in the (I2P-)(I2P2-)Al and [(I2P2-)(I2P3-)Al]2- charge states, respectively. No abrupt changes in delocalization are observed with ED and EW groups and from this we infer that ligand and metal valence p-orbitals are well-matched in energy and the absence of LMCT and MLCT bands supports the delocalized electronic structures. The MV ligand charge states (I2P-)(I2P2-)Al and [(I2P2-)(I2P3-)Al]2- show intervalence charge transfer (IVCT) transitions in the regions 6850-7740 and 7410-9780 cm-1, respectively. Alkali metal cations in solution had no effect on the IVCT bands of [(I2P2-)(I2P3-)Al]2- complexes containing -PhNMe2 or -PhF5 substituents. Minor localization of charge in [(I2P2-)(I2P3-)Al]2- was observed when -PhOMe substituents are included.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::537c90a2d3327e9d7f78a935aada56ec https://doi.org/10.1039/d0sc02812f Zobrazit plný text záznamu