ABSTRACT
The crystalline selenido germanates [Li4(H2O)16][Ge4Se10]·4.3H2O (1), [{Li4(thf)12}Ge4Se10] (2), and [Li2(H2O)8][MnGe4Se10] (3) (thf = THF = tetrahydrofuran) were obtained by an extraction of a glassy ternary phase of the nominal composition Li4Ge4Se10 (=Li2S·2GeSe2) with water (1) or THF (2) and slow evaporation of the solvent or by being layered with MnBr2 in H2O/MeOH (3), respectively. The compounds contain known selenido germanate anions, however, for the first time with Li+ counterions. This is especially remarkable for the prominent ∞3{[MnGe4Se10]2-} open-framework structure, which was reported to crystallize with (NMe4)+, Cs+, Rb+, and K+ counterions, but it has not yet been realized with the smallest alkali metal cation. Impedance spectroscopic studies on Li4Ge4Se10 classify the glassy solid as a moderate Li+ ion conductor.
ABSTRACT
[{Mn(tmeda)}(3){GeSe(3)(OMe)}(2)] (), synthesized by the reaction of [K(4)(H(2)O)(3)][Ge(2)Se(6)] with MnCl(2).4H(2)O in MeOH-tmeda (tmeda = N,N,N',N'-tetramethyl-1,2-diaminoethane), exhibits an isosceles triangular arrangement of Mn(2+) ions that are antiferromagnetically coupled with an S = 3/2 ground state.
ABSTRACT
Syntheses, structures, and physical properties of three inorganic framework compounds [K(2)(H(2)O)(3)][MnGe(4)Se(10)] (1), (NMe(4))(2)[MnSn(4)Se(10)] (2), and (NMe(4))(2)[FeSn(4)Se(10)] (3) are presented. The title compounds are based on a prominent open framework anionic structure; in these cases, however, they contain K(+), the smallest type of counterion to be included so far (1), or represent Sn analogues (2, 3). Both changes with respect to related compounds are reflected in peculiar physical properties, such as ion conductivity or relatively small band gaps.
ABSTRACT
The reactions of bis- and tris(tert-butylethynyl)benzenes with dialkylgallium hydrides afforded two different types of products. 1,4-Di(tert-butylethynyl)benzene and dialkylgallium hydrides R(2)GaH bearing relatively small substituents (R = Et, nPr) gave the expected addition products with each C triple bond C triple bond inserted into a Ga-H bond. The intact GaR(2) groups are attached to those carbon atoms which are in alpha-position to the benzene rings, and intermolecular Ga-C interactions led to the formation of one-dimensional coordination polymers. In contrast secondary reactions with the release of the corresponding trialkylgallium derivatives GaR(3) (R = Et, nPr, iPr, CH(2)tBu, tBu) were observed for all hydrogallation reactions involving the trisalkyne 1,3,5-tris(tert-butylethynyl)benzene. A similar reaction was observed upon treatment of the 1,4-bisalkyne with a dialkylgallium hydride bearing a relatively bulky substituent (R = neopentyl). Cyclophane type molecules are formed in all these cases with two or three gallium atoms in the bridging positions between both benzene rings.
