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Reactions of InCl3 with potassium salts of bifunctional tridentate (L1H2HOC6H4CH NCH2CHMeOH) and monofunctional bidentate (L2HHOC6H4CHN-i-Bu) Schiff bases in 1:1 and 1:2 molar ratio in benzene afford complexes In(L1)Cl and In(L2)2Cl, respectively. On reaction with potassium isopropoxymetallates KB(O-i-Pr)4, KAl(O-i-Pr)4, KTi(O-i-Pr)5, and KNb(O-i-Pr)6, they produce interes- ting heterobimetallic heterocyclic complexes. These are characterized by elemental (N, B, Al, Ti, and Nb) analyses, molecular weight measurements, and spectral [IR, NMR (1H, 13C, 11B, and 27Al)] studies. Probable structures are suggested for them. © 2003 Wiley Periodicals, Inc. 15:21–25, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/.hc10206

Hexaisopropoxoniobates/tantalates of lathanides of the type [Ln{(μ-OPr i ) 2 M(OPr i ) 4 } 3 ] (M = Nb, Ln = Y(1), La(2), Nd(3), Er(4), Lu(5); M = Ta, Ln = Y(6), Gd(7)) have been prepared by the reactions of LnCl 3 .3Pr i OH with three equivalents of KM(OPr i ) 6 in benzene. Reactions in 1:2 molar ratio of LnCl 3 .3Pr i OH with KTa(OPr i ) 6 yielded derivatives of the type [{(Pr i O) 3 Ta(μ-OPr i ) 3 }Ln{(μ-OPr i ) 2 Ta(OPr i ) 4 }(Cl)] (Ln = Y(8), Gd(9)), which on interactions with one equivalent of KOPr i afforded [{(Pr i O) 3 Ta(μ-OPr i ) 3 }Ln {(μ-OPr i } 2 Ta(OPr i ) 4 }(OPr i )] (Ln = Y(10), Gd(11)). All these derivatives have been characterized by elemental analyses and molecular weight measurements as well as by their spectroscopic [IR, 1 H and 1 3 C NMR (Y, La, Lu), electronic (Nd, Er)] studies. 8 9 Y NMR studies have also been carried out on derivatives (6), (8), and (10).

Growth of large area (10 cm 2 ) type II MoS 2 films by physical vapour transport is reported for the first time. The crystal growing technique used for these films, which have exceptional properties for lubrication and photovoltaic applications, is described in full. It is found that both edge island and island formation, characteristic of type 1 crystal morphology, takes place when the higher temperature end of the temperature gradient used in the preparation remains below 1070°C. When the higher temperature approaches this value, a thick film comprising exclusively of type II platelets forms on the walls of the sample vessel immediately underneath the usual type I crystallites. A model in which crystal imperfections act as nucleation centres is used to explain why crystal growth follows the observed behaviour under different temperature regimes.

Novel heterometal alkoxides of tin(IV) with the compositions [Cl4−nSn{Al(OPri)4}n] (where n = 1-3) and [Cl2Sn{Al(OBut)4}2] have been synthesized by the reactions of SnCl4 with the appropriate potassium alkoxoaluminate in the requisite molar ratio. Replacement of chloride in these derivatives has yielded heterometal (bi- or tri- ) derivatives of the types [(OR)4−nSn{Al(OPri)4}n] (R = Pri, But; n = 2 or 3) and [{Zr2(OPri)9}Sn{Al(OPri)4}3]. The new heterometal alkoxides have been characterized by elemental analyses, molecular weight measurements, IR and multinuclear (1H, 13C, 27Al and 119Sn) NMR spectral studies.