title: Thiophosphates Containing Ag+and Lone-Pair Cations with Interchiral Double Helix Show Both Ionic Conductivity and Phase Transition.
abstract: Quaternary metal thiophosphates containing second-order Jahn-Teller distorted d10Ag+and lone-pair cations, Ag3Bi(PS4)2(1), Ag7Sn(PS4)3(2), and Ag7Pb(PS4)3(3), were obtained by solid-state synthesis. The structural frameworks of 2 and 3 feature an infinite 1-D interchiral double helix∞1(Ag3P2S11), which is rare in inorganic compounds. Compound 3 undergoes a significant first-order structural phase transition from monoclinic to hexagonal at ∼204 °C. This can be ascribed to the significant mismatch in the expansion coefficients between Pb-S (Ag-S) and P-S bonds evaluated by bond valence theory. The three compounds are Ag+ionic conductors, and Ag+ion migration pathways are proposed by calculating maps of low bond valence mismatch. Moreover, the optical properties of the three compounds were studied, and electronic structure calculations were performed. The combination of second-order Jahn-Teller distorted d10cation and lone-pair cation provides a new strategy to explore new metal thiophosphates with interesting structures and promising properties.
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Yu-Hang
authors.initials: YH
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Hui-Yi
authors.initials: HY
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Ming-Jian
authors.initials: MJ
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Bin-Wen
authors.initials: BW
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Guo-Cong
authors.identifier: http://orcid.org/0000-0002-7450-9702
authors.initials: GC
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Jin-Shun
authors.initials: JS
authors.lastname: Huang