(BEDT-TTF)2Cu2(HCOO)5: An Organic-Inorganic Hybrid Conducting Magnet

Bin Zhang; Yan Zhang; Zheming Wang; Zengqiang Gao; Deliang Yang; Dongwei Wang; Yanjun Guo; Daoben Zhu

doi:10.1002/open.201700041

(BEDT-TTF)₂Cu₂(HCOO)₅: An Organic-Inorganic Hybrid Conducting Magnet

ChemistryOpen. 2017 Apr 19;6(3):320-324. doi: 10.1002/open.201700041. eCollection 2017 Jun.

Authors

Bin Zhang¹, Yan Zhang², Zheming Wang³, Zengqiang Gao⁴, Deliang Yang⁵, Dongwei Wang⁶, Yanjun Guo⁶, Daoben Zhu¹

Affiliations

¹ Organic Solid Laboratory, CAS Research/Education Center for Excellence in Molecular Sciences, CMS & BNLMS, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P.R. China.
² Institute of Condensed Matter and Material Physics, School of Physics Peking University Beijing 100871 P.R. China.
³ BNLMS, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering Peking University, Beijing, 100871 (P.R. China).
⁴ Beijing Synchrotron Radiation Facility, Institute of High-Energy Physics Chinese Academy of Sciences Beijing 100047 P.R. China.
⁵ CMS & BNLMS, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P.R. China.
⁶ CAS Key Laboratory of Standardization and Measurement for Nanotechnology National Center for Nanoscience and Technology Beijing 100190 P.R. China.

Abstract

A dual-functional organic-inorganic hybrid (BEDT-TTF)₂Cu₂(HCOO)₅ (1) (BEDT-TTF=bis(ethylenedithio)tetrathiafulvalene) was obtained through the electrochemical oxidation of neutral BEDT-TTF in the presence of an ammonium salt of the one-dimensional copper-formate framework [(C₂H₅)₃NH]₂Cu₂(HCOO)₅ in a C₆H₅Cl-C₂H₅OH solution. Compound 1 was composed of organic donor BEDT-TTF⁺⁰⋅⁵ in a θ-phase arrangement and Jahn-Teller distorted (4,4) grid anion sheets [Cu₂(HCOO)₅^-] _n with S=1/2. We identified the material as a semiconductor with values of σ_300K=10^-1 S cm^-1. The anion sheet is a coordination isomer of [Cu₂(HCOO)₅^-] _n and, compared with the starting material, shows antiferromagnetic behavior as the well-known inorganic Cu-O, Co-O square layers for creating inorganic conducting magnets. Long-range antiferromagnetic ordering was observed at 8.0 K.

Keywords: Jahn–Teller distortion; antiferromagnetism; cation templates; charge-transfer salts; square lattices.