Synthesis, Structure And Properties Of Polymetal Selenide/Tellurium Containing Organic Ligand

The subject is to synthesis and analyzes the structure and properties of polymental selenide containing organic ligand. By now the polymental selenides have been the hot-point in solid chemistry because of their special physical and chemical characters result from low-dimension structures which have great applicated prospects and many potential economic benefits.In this dissertation, we did the summary of the development of multi-component metal chalcogenides. Besides, we did analysis, study and induce the synthesis methods, structure rules and characters applications of such compounds.Low-temperature solvothermal technique growth normally produce compounds which have low-demension structures (0-D,1-D,2-D) which are metastable state in thermodynamics. We have done some research on the new orientation of synthesis-solvothermal technique to synthesis comlound AxMyLnM'y'Qz in which M= transitional metal; M'= main-group metal;Q=S,Se,Te; L= poly-teeth-organic-ligand (n≥0) according to ideas of molecule designing. Through many erperiments six new chalcogenide crystals have been synthesized and two of them which are K2MnSnTe4 and [Mn(en)3](Hen)SbSe4 have both been determinated by single crystal X-ray diffraction. [Mn(en)3](Hen)SbSe4 belongs to triclinic space group P-1 with the unit cell parameters, a = 0.88895(18)nm, b = 0.96509(19)nm, c = 1.4530, α = 104.64(3)°, β = 92.23(3)°, γ = 110.62(3)°, V = 1.1175(4) nm 3, Z = 4, Dc = 3.281 Mg/m3, μ= 12.471 mm-1, F(000) = 1019. R1 = 0.1666, wR2 = 0.4125。The crystal which contains separately (SbSe4)3-, [Mn(en)3]2+ and (Hen)1+ is piled up by electrostatic power. We can't obtain the accurate crystal structure of K2MnSnTe4 provisionally because of some structure disfigurements. But it had been presumed that K2MnSnTe4 has the same crystal structure with K2MnSnSe4.Studies on diffuse reflective spectra for the both powder samples suggested that these compounds are both semiconductors, with band gap of [Mn(en)3](Hen)SbSe4 = 1.52eV and K2MnSnTe4 = 1.75eV. The result of TG analysis indicated that [Mn(en)3](Hen)SbSe4 has high thermal stability.