Release Time:2019-03-11  Hits:

Indexed by: Journal Article

Date of Publication: 2017-11-01

Journal: JOURNAL OF PHYSICS-CONDENSED MATTER

Included Journals: Scopus、PubMed、EI、SCIE

Volume: 29

Issue: 43

Page Number: 435802

ISSN: 0953-8984

Key Words: magnetic anisotropy; metallocene; spin-orbit coupling

Abstract: The stability, electronic structure and non-collinear magnetic properties of a series of 5d metallocenes, namely, two cyclopentadienyl (Cp) rings sandwiched with a single 5d transition metal atom, are investigated. Our first-principles calculations reveal that Cp rings not only provide a suitable ligand environment for metal atoms, but also result in tunable magnetism depending on the transition metal element. Among them, HfCp2 and WCp2 show a high preference for the magnetization axis perpendicular to the Cp plane, with large magnetic anisotropy energies (MAEs) around 10 meV. We further consider triple decker metallocenes (M2Cp3), and find a huge MAE of above 60 meV in Ta2Cp3. The orbital energy split and shifts induced by composition change in metallocenes is mainly responsible for the significant MAE enhancement. By choosing a suitable crystal field for transition metal atoms, we pave a feasible pathway for designing promising building blocks of future magnetic storage devices.