Exchange bias in Ni 4 single-molecule magnets

Autor:	David N. Hendrickson, Arnold L. Rheingold, Wolfgang Wernsdorfer, George Christou, Rachel S. Edwards, Lev N. Zakharov, En-Che Yang, S. Maccagnano, Stephen Hill, Motohiro Nakano
Rok vydání:	2003
Předmět:	Condensed matter physics Chemistry Nanomagnet law.invention Inorganic Chemistry Magnetization Crystallography Exchange bias Ferromagnetism law Materials Chemistry Molecule Physical and Theoretical Chemistry Electron paramagnetic resonance Ground state Single crystal
Zdroj:	Polyhedron. 22:1727-1733
ISSN:	0277-5387
Popis:	The syntheses and physical properties are reported for three single-molecule magnets (SMMs) with the composition [Ni(hmp)(ROH)Cl]4, where R is CH3 (complex 1), CH2CH3 (complex 2) or CH2CH2C(CH3)3 (complex 3) and hmp− is the monoanion of 2-hydroxymethylpyridine. The core of each complex is a distorted cube formed by four NiII ions and four alkoxide hmp− oxygen atoms at alternating corners. Ferromagnetic exchange interactions give a S=4 ground state. Single crystal high-frequency EPR spectra clearly indicate that each of the complexes has a S=4 ground state and that there is negative magnetoanisotropy, where D is negative for the axial zero-field splitting DŜz2. Magnetization versus magnetic field measurements made on single crystals with a micro-SQUID magnetometer indicate these Ni4 complexes are SMMs. Exchange bias is seen in the magnetization hysteresis loops for complexes 1 and 2.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f98aabbb2375172ddbf84fce9b329902 https://doi.org/10.1016/s0277-5387(03)00149-9 Zobrazit plný text záznamu Full Text from ScienceDirect