Fe0.36(4)Pd0.64(4)Se2: Magnetic Spin-Glass Polymorph of FeSe2 and PdSe2 Stable at Ambient Pressure

Jianjun Tian; Valentin N Ivanovski; David Szalda; Hechang Lei; Aifeng Wang; Yu Liu; Weifeng Zhang; Vasil Koteski; Cedomir Petrovic

doi:10.1021/acs.inorgchem.8b03089

Fe_0.36(4)Pd_0.64(4)Se₂: Magnetic Spin-Glass Polymorph of FeSe₂ and PdSe₂ Stable at Ambient Pressure

Inorg Chem. 2019 Mar 4;58(5):3107-3114. doi: 10.1021/acs.inorgchem.8b03089. Epub 2019 Feb 19.

Authors

Jianjun Tian^{1

2}, Valentin N Ivanovski³, David Szalda⁴, Hechang Lei⁵, Aifeng Wang¹, Yu Liu¹, Weifeng Zhang², Vasil Koteski³, Cedomir Petrovic¹

Affiliations

¹ Condensed Matter Physics and Materials Science Department , Brookhaven National Laboratory , Upton , New York 11973 , United States.
² Henan Key Laboratory of Photovoltaic Materials and School of Physics & Electronics , Henan University , Kaifeng 475004 , China.
³ Vinca Institute of Nuclear Sciences , University of Belgrade , Belgrade 11001 , Serbia.
⁴ Department of Natural Sciences , Baruch College, CUNY , New York , New York 10010-5585 , United States.
⁵ Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices , Renmin University of China , Beijing 100872 , China.

PMID: 30777749
DOI: 10.1021/acs.inorgchem.8b03089

Abstract

We report the synthesis and characterization of Fe_0.36(4)Pd_0.64(4)Se₂ with a pyrite-type structure. Fe_0.36(4)Pd_0.64(4)Se₂ was synthesized using ambient pressure flux crystal growth methods even though the space group Pa3 is high-pressure polymorph for both FeSe₂ and PdSe₂. Combined experimental and theoretical analysis reveal magnetic spin glass state below 23 K in 1000 Oe that stems from random Fe/Pd occupancies on the same atomic site. The frozen-in magnetic randomness contributes significantly to electronic transport. Electronic structure calculations confirm dominant d-electron character of hybridized bands and large density of states near the Fermi level. Flux-grown single crystal alloys in Pd-Fe-Se atomic system therefore open new pathway for exploring different polymorphs in crystal structures and their novel properties.