A series of new lanthanoid thioantimonates: a rare example of organic-decorated cationic lanthanoid thioantimonate chains based on asymmetric dinuclear lanthanide complexes

Abstract

A series of new lanthanoid thioantimonates [Ln(teta)₂]SbS₄ [teta = triethylenetetramine; Ln = Eu (1), Gd (2), Er (3)], {[Ln(tepa)]₂[μ₂-Sb^IIIS₃](μ₂-OH)}₂{[Ln(tepa)]₂(μ₂-OH)₂(Sb^VS₄)₂}Cl₂ [tepa = tetraethylene-pentamine; Ln = Y(4), Eu(5), Er(6)], and [Gd₂(tepa)₂(μ₂-OH)₂(μ₂-SbS₄)]Cl·0.25H₂O (7) were synthesized via reactions of Sb, S and LnCl₃ in teta or tepa under solvothermal conditions and were structurally characterized. Compounds 1–3 consist of isolated [Ln(teta)₄]³⁺ cations and tetrahedral [SbS₄]³⁻ anions. Compounds 4–6 contain heterometallic mixed amino-thiocluster cations {[Ln(tepa)]₂[μ₂-SbS₃](μ₂-OH)}²⁺, heterometallic anions {[Ln₂(tepa)₂(μ₂-OH)₂](SbS₄)₂}²⁻ and free Cl⁻ ions, which provide a rare example of the coexistence of noncondensed pyramidal [Sb^IIIS₃]³⁻ and tetrahedral [Sb^VS₄]³⁻ anions in a single thioantimonate. 7 consists of a 1-D polymeric cation [Gd₂(tepa)₂(μ₂-OH)₂(μ₂-SbS₄)]⁺, constructed through the linkage of asymmetric dinuclear gadolinium complex [Gd₂(tepa)₂(μ₂-OH)₂]⁴⁺ cations, tetrahedral [Sb^VS₄]³⁻ anions and a Cl⁻ ion and water molecule, which represents a rare example of organic-decorated cationic lanthanoid thioantimonate chains based on asymmetric dinuclear lanthanide complexes. The present compounds exhibit semiconducting properties with absorption band edges between 2.00 and 3.03 eV.