Muons and magnets

Research group

Research theme

Sub department

About

Related research groups

[Ni(HF2)(3-Clpy)4]BF4 (py = pyridine): evidence for spin exchange along strongly distorted F···H···F- bridges in a one-dimensional polymeric chain.

Inorg Chem 51:14 (2012) 7520-7528

Authors:

Jamie L Manson, Adora G Baldwin, Brian L Scott, Jesper Bendix, Rico E Del Sesto, Paul A Goddard, Yoshimitsu Kohama, Hope E Tran, Saman Ghannadzadeh, John Singleton, Tom Lancaster, Johannes S Möller, Stephen J Blundell, Francis L Pratt, Vivien S Zapf, Jinhee Kang, Changhoon Lee, Myung-Hwan Whangbo, Christopher Baines

Abstract:

[Ni(HF(2))(3-Clpy)(4)]BF(4) (py = pyridine) is a simple one-dimensional (1D) coordination polymer composed of compressed NiN(4)F(2) octahedra that form chains with bridging HF(2)(-) ligands. In spite of significant distortion of the HF(2)(-) bridge, a quasi-1D antiferromagnetic (AFM) behavior was observed with J(FHF) = 4.86 K.
More details from the publisher
More details

Superconductivity in New Materials, Vol. 4, volume edited by Z. Fisk and H.R. Ott

Contemporary Physics Taylor & Francis 53:4 (2012) 394-395
More details from the publisher

Influence of HF2- geometry on magnetic interactions elucidated from polymorphs of the metal-organic framework [Ni(HF2)(pyz)2]PF6 (pyz = pyrazine).

Dalton Trans 41:24 (2012) 7235-7243

Authors:

Jamie L Manson, Kimberly E Carreiro, Saul H Lapidus, Peter W Stephens, Paul A Goddard, Rico E Del Sesto, Jesper Bendix, Saman Ghannadzadeh, Isabel Franke, John Singleton, Tom Lancaster, Johannes S Möller, Peter J Baker, Francis L Pratt, Stephen J Blundell, Jinhee Kang, Changhoon Lee, Myung-Hwan Whangbo

Abstract:

A tetragonal polymorph of [Ni(HF(2))(pyz)(2)]PF(6) (designated β) is isomorphic to its SbF(6)-congener at 295 K and features linear Ni-FHF-Ni pillars. Enhancements in the spin exchange (J(FHF) = 7.7 K), Néel temperature (T(N) = 7 K), and critical field (B(c) = 24 T) were found relative to monoclinic α-PF(6). DFT reveals that the HF(2)(-) bridges are significantly better mediators of magnetic exchange than pyz (J(pyz)), where J(FHF) ≈ 3J(pyz), thus leading to quasi-1D behavior. Spin density resides on all atoms of the HF(2)(-) bridge whereas N-donor atoms of the pyz ring bear most of the density.
More details from the publisher
More details

Magnetism: A Very Short Introduction

Oxford University Press (OUP), 2012
More details from the publisher

Persistent dynamics in the S=1/2 quasi-one-dimensional chain compound Rb 4Cu(MoO 4) 3 probed with muon-spin relaxation

Physical Review B - Condensed Matter and Materials Physics 85:18 (2012)

Authors:

T Lancaster, PJ Baker, FL Pratt, SJ Blundell, W Hayes, D Prabhakaran

Abstract:

We report the results of muon-spin relaxation measurements on the low-dimensional antiferromagnet Rb 4Cu(MoO 4) 3. No long-range magnetic order is observed down to 50 mK implying a ratio T N/J<0.005 (where J is the principal exchange strength along the spin chains) and an effective ratio of interchain to intrachain exchange of |J ⊥/J|<2×10 -3, making the material an excellent realization of a one-dimensional quantum Heisenberg antiferromagnet. We probe the persistent spin excitations at low temperatures and find that ballistic spin transport dominates the excitations detected below 0.3 K. © 2012 American Physical Society.
More details from the publisher
More details