Novel Copper(I)‐Thioantimonates(III): Solvothermal Synthesis,Crystal Structures,Thermal Stability and Magnetic Properties of (C2N2H10)0.5Cu2SbS3, (C3N2H12)0.5Cu2SbS3, and (C4N2H14)0.5Cu2SbS3

The novel copper(I)‐thioantimonates(III) (enH₂²⁺)_0.5Cu₂SbS₃ ( I ) (en = ethylendiamine), (1, 3‐DAPH₂²⁺)_0.5Cu₂SbS₃ ( II ) (1, 3‐DAP = 1, 3 diaminopropane) and (1, 4‐DABH₂²⁺)_0.5Cu₂SbS₃ ( III ) (1, 4‐DAB = 1, 4‐diaminobutane) were synthesized under solvothermal conditions reacting Sb₂S₃, CuCl₂·2H₂O, S with the amines. The compounds crystallize in the monoclinic space group P2₁/n. The primary building units are a SbS₃ trigonal pyramid and two distorted CuS₃ units. In the structures the SbS₃ pyramid is connected to six CuS₃ moieties and every S atom has bonds to one Sb atom and to two Cu atoms. Further interconnection leads to the formation of ten‐membered (10 MR) Cu₃Sb₂S₅ and six‐membered (6 MR) Cu₂SbS₃ rings. Every 10 MR is condensed to four 10 MR and four 6 MR to form a single layer within the (010) plane. Two such single layers are connected to a double layer thus forming the final [Cu₂SbS₃]^— layered anion. The [CuSbS₃]^— protonated amines are located between the layers and the interlayer spacing depends on the size and orientation of these amines. Between the Sb atom and one Cu atom a remarkable short distance of about 2.7Å is observed. At elevated temperatures the compounds decompose into CuSbS₂ and Cu₃SbS₄ suggesting a complex redox reaction. Diamagnetic susceptibilities indicate the copper(I) in the metal sulfide frameworks. All three compounds are semiconductors with intermediate band gaps of about 2 eV.