Synthesis, Structure, and Properties of the Layered Oxyselenide Ba2CuO2Cu2Se2

Wenmin Li; Zhaoming Fu; Xiancheng Wang; Jun Zhang; Min Liu; Jianfa Zhao; Meiling Jin; Guoqiang Zhao; Guangyang Dai; Zheng Deng; Sijia Zhang; Shaomin Feng; Zhiwei Hu; Qingzhen Huang; Hongji Lin; Chien-Te Chen; Yifeng Yang; Changqing Jin

doi:10.1021/acs.inorgchem.8b00171

Synthesis, Structure, and Properties of the Layered Oxyselenide Ba₂CuO₂Cu₂Se₂

Inorg Chem. 2018 May 7;57(9):5108-5113. doi: 10.1021/acs.inorgchem.8b00171. Epub 2018 Apr 9.

Authors

Wenmin Li^{1

2}, Zhaoming Fu¹, Xiancheng Wang¹, Jun Zhang^{1

2}, Min Liu^{1

2}, Jianfa Zhao^{1

2}, Meiling Jin^{1

2}, Guoqiang Zhao^{1

2}, Guangyang Dai^{1

2}, Zheng Deng¹, Sijia Zhang¹, Shaomin Feng¹, Zhiwei Hu³, Qingzhen Huang⁴, Hongji Lin⁵, Chien-Te Chen⁵, Yifeng Yang^{1

2

6}, Changqing Jin^{1

2

6}

Affiliations

¹ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
² School of Physics , University of Chinese Academy of Sciences , Beijing 100190 , China.
³ Max Plank Institute for Chemical Physics of Solids , Nöthnitzer Strasse 40 , D-01187 Dresden , Germany.
⁴ Center for Neutron Research , National Institute of Standards and Technology , Gaithersburg , Maryland 20899-6102 , United States.
⁵ National Synchrotron Radiation Research Center (NSRRC) , 101 Hsin-Ann Road , Hsinchu 30076 , Taiwan.
⁶ Collaborative Innovation Center of Quantum Matter , Beijing 100190 , China.

PMID: 29629763
DOI: 10.1021/acs.inorgchem.8b00171

Abstract

A new layered oxyselenide, Ba₂CuO₂Cu₂Se₂, was synthesized under high-pressure and high-temperature conditions and was characterized via structural, magnetic, and transport measurements. It crystallizes into space group I4/ mmm and consists of a square lattice of [CuO₂] planes and antifluorite-type [Cu₂Se₂] layers, which are alternately stacked along the c axis. The lattice parameters are obtained as a = b = 4.0885 Å and c = 19.6887 Å. The Cu-O bond length is given by half of the lattice constant a, i.e., 2.0443 Å. Ba₂CuO₂Cu₂Se₂ is a semiconductor with a resistivity of ∼18 mΩ·cm at room temperature. No magnetic transition was found in the measured temperature range, and the Curie-Weiss temperature was obtained as -0.2 K, suggesting a very weak exchange interaction. The DFT+ U_eff calculation demonstrates that the band gap is about 0.2 eV for the supposed antiferromagnetic order, and the density of state near the top of the valence band is mainly contributed from the Se 4p electrons.