Chemical Synthesis Of Designed Precursors With Thiolate Ligands To Binary And Ternary Semiconducting Crystalline Materials

Treatment of [Et₄N][GaCl₄] with four equivalents of NaQR in methanol afforded the substitution complexes [Et₄N][Ga(QR)₄] (QR = SC₆H₄Me-p 1, QR = SePh 3), while the indium analogues [Et₄N][In(SC₆H4Me-p)₄] (2) was prepared by the reaction of InCl₃·3H₂O and NaSC6H4Me-p in the presence of [Et₄N]Cl·xH₂O. The structures of these three complexes, as determined by single-crystal X-ray diffraction, feature well-separated cations and anions with the metal centers of the anions tetrahedrally coordinated to four thiolate or selenolate ligands. The thermal stability of the three complexes was studied by thermal gravimetric analysis.Metathesis reaction between equimolar amount of [Et₄N][GaCl₄] and Na₂edt in methanol resulted in the formation of the dichloro complex [Et₄N][Ga(edt)Cl₂] (4), whereas reaction of [Et₄N][GaCl₄] with two equivalents of Na₂edt in methanol gave the complex [Et₄N][Ga(edt)₂] (5) which can act as a metalloligand. Treatment of 5 with M(PPh₃)₂NO₃ in DMF/CH₂Cl₂ afforded the heterobimetallic complexes [Ga(edt)₂M(PPh₃)₂] (M =Cu 6, Ag 7) in moderate yields. The structures of 4-7 were determined by single-crystal X-ray diffraction analyses. Both [Ga(edt)Cl₂]^- and [Ga(edt)2]^- anions have a distorted tetrahedral geometry. The former consists of one five-membered ring formed by chelating dithiolate and two terminal chloride atoms while the latter consists of two five-membered rings formed by two the chelating dithiolates. Complexes 6 and 7 consist of metalloligand [Ga(edt)₂]^- anion chelated to [M(PPh₃)₂]⁺ via the sulfur atoms. Both tetrahedrally coordinated Ga and Cu(Ag) atoms are bridged by two sulfur atoms, forming a planar"MS₂Ga"(M = Cu, Ag) core. Thermogravimetry analysis revealed that heterobimetallic complexes 6 and 8 decomposed to give the corresponding ternary metal sulfide materials.Treatment of a slurry of an equimolar mixture of [Sn(edt)₂] (edt = ethane-1,2- dithiolate) and [Et₄N]Cl^-xH₂O with CuI in the presence of PPh₃ gave a tetranuclear compound, [Sn(edt)₂Cl(μ-I)(μ₃-I)(CuPPh₃)₃] (8), which consists of a rectangular-pyramidal [Sn(edt)₂Cl]^- moiety ligated by three [Cu(PPh₃)]⁺ fragments via the sulfur atoms of the edt₂^- ligands. Treatment of a slurry of [Sn(edt)₂] and excess [Et₄N]Br with [Cu(MeCN)₄][PF₆] in the presence of PPh3 afforded a pentanuclear compound, [Sn(edt)₂(μ-Br)₂(μ₃-Br)₂(CuPPh₃)₄] (9), which comprises two [(CuPPh₃)₂(μ-Br)]⁺ fragments symmetrically ligating an octahedral trans-[Sn(edt)₂Br₂]^2- moiety via the sulfur and bromide atoms. Reaction of [Sn(edt)₂] with [Cu(MeCN)₄][PF₆] and PPh₃ in a mixed MeCN/CH₂Cl₂ solution yielded a novel octanuclear compound, [{Sn(edt)₂}₃(μ-OH)₃Cu₅(PPh₃)₈][PF₆]₂ (10), which may be described as a triangular [{Sn(edt)₂}₃(μ-OH)₃]^3- core chelated by three [Cu(PPh₃)₂]⁺ and capped by two [Cu(PPh₃)]⁺ species. The luminescent properties of compounds 8, 9, and 10 were investigated in CH₂Cl₂ solution at room temperature. Upon excitation atλ> 360 nm, these compounds are luminescent in CH₂Cl₂ solution with emission with maxima at 422, 515, and 494 nm, respectively.By using of the density functional theory (DFT) B3LYP method, the novel complexes C₂H₄Cl₂GaS₂(1-) and C₄H₈GaS₄(1-) have been theoretically calculated. The analysis of the vibration frequency and natural bond orbital (NBO) have also been carried on them based on the optimized geometries. We presented and compared their energy property, charge contribution, orbital and bonded properties and predicted their infrared spectrums. The results showed that compared to the complex 2, complex 1 has the bigger stability and two Cl atoms in molecule 1 has few contribution to the frontier molecular orbital. It is also found that both the infrared spectrums and the NBOs of them are similar. In addition, the inner electrons and orbits of Ga do not take part in bonding as well as its 3d orbit.