Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes

Shalini Tripathi; Shefali Vaidya; Naushad Ahmed; Emil Andreasen Klahn; Huibo Cao; Lena Spillecke; Changhyun Koo; Sven Spachmann; Rüdiger Klingeler; Gopalan Rajaraman; Jacob Overgaard; Maheswaran Shanmugam

doi:10.1016/j.xcrp.2021.100404

Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes

Shalini Tripathi
, Shefali Vaidya
, Naushad Ahmed
, Emil Andreasen Klahn
, Huibo Cao
, Lena Spillecke
, Changhyun Koo
, Sven Spachmann
, Rüdiger Klingeler
, Gopalan Rajaraman
, Jacob Overgaard
, Maheswaran Shanmugam

Single Crystal Diffraction

Research output: Contribution to journal › Article › peer-review

32 Scopus citations

Abstract

Stabilizing an easy axis of magnetization in an octahedral Co(II) complex is an extremely challenging task, which is evident from reports that more than 90% possess easy-plane anisotropy. Here, we report a six-coordinate complex, [Co(L₁)₄(Cl)₂] (1, L₁ = thiourea [H₂N-CS-NH₂]), that exhibits a D value of −63(10) cm⁻¹. The presence of an easy axis of magnetization associated with 1 is experimentally proven by detailed magnetic studies and polarized neutron diffraction studies, and the experimental observations are well corroborated by theoretical calculations. From the combined experimental and theoretical investigations (on 1 and many model systems), we unveil the parameters that control stabilization of negative D in a thermodynamically favorable and air-stable Co(II) ion in the common distorted octahedral geometry. This study paves the way for overcoming the current impediments to alleviate the easy axis of magnetization using rational ligand choice.

Original language	English
Article number	100404
Journal	Cell Reports Physical Science
Volume	2
Issue number	4
DOIs	https://doi.org/10.1016/j.xcrp.2021.100404
State	Published - Apr 21 2021

Funding

M.S. thanks SERB ( CRG/2019/004185 and SPR/2019/001145 ), CSIR ( 01(2933)/18/EMR-II ), and IIT Bombay for financial assistance. G.R. thanks SERB for funding ( CRG/2018/000430 , DST/SJF/CSA-03/2018-10 , and SB/SJF/2019-20/12 ). J.O. and E.A.K. thank the Danish National Research Foundation ( DNRF-93 ) and the Villum Foundation for financial support. Affiliation with the Center for Integrated Materials Research (iMAT) at Aarhus University is gratefully acknowledged (J.O.).The authors gratefully acknowledge the beamtime at the high-flux isotope reactor (HFIR) and Laboratoire Leon-Brillouin. Bryan C. Chakoumakos provided logistical support for the experiments at the HFIR. A portion of this research used resources at the HFIR, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. This work is supported by the Deutsche Forschungsgemeinschaft (DFG; German Research Foundation) under Germany’s Excellence Strategy EXC2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster ), by the BMBF via the SpinFun project ( 13XP5088 ), and by the HLD at HZDR , a member of the European Magnetic Field Laboratory (EMFL). We thank Dr. Marc Uhlarz for technical support during the pulsed-field magnetization measurements. M.S. thanks SERB (CRG/2019/004185 and SPR/2019/001145), CSIR (01(2933)/18/EMR-II), and IIT Bombay for financial assistance. G.R. thanks SERB for funding (CRG/2018/000430, DST/SJF/CSA-03/2018-10, and SB/SJF/2019-20/12). J.O. and E.A.K. thank the Danish National Research Foundation (DNRF-93) and the Villum Foundation for financial support. Affiliation with the Center for Integrated Materials Research (iMAT) at Aarhus University is gratefully acknowledged (J.O.).The authors gratefully acknowledge the beamtime at the high-flux isotope reactor (HFIR) and Laboratoire Leon-Brillouin. Bryan C. Chakoumakos provided logistical support for the experiments at the HFIR. A portion of this research used resources at the HFIR, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. This work is supported by the Deutsche Forschungsgemeinschaft (DFG; German Research Foundation) under Germany's Excellence Strategy EXC2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster), by the BMBF via the SpinFun project (13XP5088), and by the HLD at HZDR, a member of the European Magnetic Field Laboratory (EMFL). We thank Dr. Marc Uhlarz for technical support during the pulsed-field magnetization measurements. S.T. and S.V. synthesized and characterized the compounds and modeled magnetic data. S.T. performed the computational calculations. N.A. performed MOLCAS calculations under the supervision of G.R. E.A.K. performed PND measurements with H.C. under the supervision of J.O. L.S. performed static field magnetization measurements and performed QMC simulations under the supervision of C.K. and R.K. S.S. performed pulsed-field magnetization measurements supervised by R.K. M.S. designed and supervised the work. All authors contributed to writing the manuscript. The authors declare no competing interests.

Keywords

ORCA
cobalt
coordination complex
magnetic anisotropy
magnetism
polarized neutron diffraction
single-molecule magnet

Access to Document

10.1016/j.xcrp.2021.100404

Cite this

Tripathi, S., Vaidya, S., Ahmed, N., Andreasen Klahn, E., Cao, H., Spillecke, L., Koo, C., Spachmann, S., Klingeler, R., Rajaraman, G., Overgaard, J., & Shanmugam, M. (2021). Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes. Cell Reports Physical Science, 2(4), Article 100404. https://doi.org/10.1016/j.xcrp.2021.100404

@article{c68901ebfc7e46c2acf5bfe37a523b87,

title = "Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes",

abstract = "Stabilizing an easy axis of magnetization in an octahedral Co(II) complex is an extremely challenging task, which is evident from reports that more than 90\% possess easy-plane anisotropy. Here, we report a six-coordinate complex, [Co(L1)4(Cl)2] (1, L1 = thiourea [H2N-CS-NH2]), that exhibits a D value of −63(10) cm−1. The presence of an easy axis of magnetization associated with 1 is experimentally proven by detailed magnetic studies and polarized neutron diffraction studies, and the experimental observations are well corroborated by theoretical calculations. From the combined experimental and theoretical investigations (on 1 and many model systems), we unveil the parameters that control stabilization of negative D in a thermodynamically favorable and air-stable Co(II) ion in the common distorted octahedral geometry. This study paves the way for overcoming the current impediments to alleviate the easy axis of magnetization using rational ligand choice.",

keywords = "ORCA, cobalt, coordination complex, magnetic anisotropy, magnetism, polarized neutron diffraction, single-molecule magnet",

author = "Shalini Tripathi and Shefali Vaidya and Naushad Ahmed and \{Andreasen Klahn\}, Emil and Huibo Cao and Lena Spillecke and Changhyun Koo and Sven Spachmann and R{\"u}diger Klingeler and Gopalan Rajaraman and Jacob Overgaard and Maheswaran Shanmugam",

note = "Publisher Copyright: {\textcopyright} 2021 The Author(s)",

year = "2021",

month = apr,

day = "21",

doi = "10.1016/j.xcrp.2021.100404",

language = "English",

volume = "2",

journal = "Cell Reports Physical Science",

issn = "2666-3864",

publisher = "Elsevier",

number = "4",

}

TY - JOUR

T1 - Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes

AU - Tripathi, Shalini

AU - Vaidya, Shefali

AU - Ahmed, Naushad

AU - Andreasen Klahn, Emil

AU - Cao, Huibo

AU - Spillecke, Lena

AU - Koo, Changhyun

AU - Spachmann, Sven

AU - Klingeler, Rüdiger

AU - Rajaraman, Gopalan

AU - Overgaard, Jacob

AU - Shanmugam, Maheswaran

PY - 2021/4/21

Y1 - 2021/4/21

N2 - Stabilizing an easy axis of magnetization in an octahedral Co(II) complex is an extremely challenging task, which is evident from reports that more than 90% possess easy-plane anisotropy. Here, we report a six-coordinate complex, [Co(L1)4(Cl)2] (1, L1 = thiourea [H2N-CS-NH2]), that exhibits a D value of −63(10) cm−1. The presence of an easy axis of magnetization associated with 1 is experimentally proven by detailed magnetic studies and polarized neutron diffraction studies, and the experimental observations are well corroborated by theoretical calculations. From the combined experimental and theoretical investigations (on 1 and many model systems), we unveil the parameters that control stabilization of negative D in a thermodynamically favorable and air-stable Co(II) ion in the common distorted octahedral geometry. This study paves the way for overcoming the current impediments to alleviate the easy axis of magnetization using rational ligand choice.

AB - Stabilizing an easy axis of magnetization in an octahedral Co(II) complex is an extremely challenging task, which is evident from reports that more than 90% possess easy-plane anisotropy. Here, we report a six-coordinate complex, [Co(L1)4(Cl)2] (1, L1 = thiourea [H2N-CS-NH2]), that exhibits a D value of −63(10) cm−1. The presence of an easy axis of magnetization associated with 1 is experimentally proven by detailed magnetic studies and polarized neutron diffraction studies, and the experimental observations are well corroborated by theoretical calculations. From the combined experimental and theoretical investigations (on 1 and many model systems), we unveil the parameters that control stabilization of negative D in a thermodynamically favorable and air-stable Co(II) ion in the common distorted octahedral geometry. This study paves the way for overcoming the current impediments to alleviate the easy axis of magnetization using rational ligand choice.

KW - ORCA

KW - cobalt

KW - coordination complex

KW - magnetic anisotropy

KW - magnetism

KW - polarized neutron diffraction

KW - single-molecule magnet

UR - https://www.scopus.com/pages/publications/85104419262

U2 - 10.1016/j.xcrp.2021.100404

DO - 10.1016/j.xcrp.2021.100404

M3 - Article

AN - SCOPUS:85104419262

SN - 2666-3864

VL - 2

JO - Cell Reports Physical Science

JF - Cell Reports Physical Science

IS - 4

M1 - 100404

ER -

Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes

Abstract

Funding

Keywords

Access to Document

Other files and links

Fingerprint

Cite this