Significant Enhancement of Energy Barriers in Dinuclear Dysprosium Single-Molecule Magnets Through Electron-Withdrawing Effects

Autor:	Ilia Korobkov, Muralee Murugesu, Liviu F. Chibotaru, Veacheslav Vieru, Gabriel Brunet, Fatemah Habib
Rok vydání:	2013
Předmět:	Ligand chemistry.chemical_element General Chemistry Biochemistry Catalysis Solvent chemistry.chemical_compound Crystallography Colloid and Surface Chemistry chemistry Ab initio quantum chemistry methods Computational chemistry Excited state Diethylenetriamine Dysprosium Polar effect Molecule
Zdroj:	Journal of the American Chemical Society. 135:13242-13245
ISSN:	1520-5126 0002-7863
DOI:	10.1021/ja404846s
Popis:	The effect of electron-withdrawing ligands on the energy barriers of Single-Molecule Magnets (SMMs) is investigated. By introducing highly electron-withdrawing atoms on targeted ligands, the energy barrier was significantly enhanced. The structural and magnetic properties of five novel SMMs based on a dinuclear {Dy2} phenoxo-bridged motif are explored and compared with a previously studied {Dy2} SMM (1). All complexes share the formula [Dy2(valdien)2(L)2]·solvent, where H2valdien = N1,N3-bis(3-methoxysalicylidene) diethylenetriamine, the terminal ligand L = NO3(-) (1), CH3COO(-) (2), ClCH2COO(-) (3), Cl2CHCOO(-) (4), CH3COCHCOCH3(-) (5), CF3COCHCOCF3(-) (6), and solvent = 0.5 MeOH (4), 2 CH2Cl2 (5). Systematic increase of the barrier was observed for all complexes with the most drastic increase seen in 6 when the acac ligand of 5 was fluorinated resulting in a 7-fold enhancement of the anisotropic barrier. Ab initio calculations reveal more axial g tensors as well as higher energy first excited Kramers doublets in 4 and 6 leading to higher energy barriers for those complexes.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bc00eceed5d9933f2e9580f22d9e0a3d https://doi.org/10.1021/ja404846s Zobrazit plný text záznamu