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Insulating materials can in principle be made metallic by applying pressure. In the case of pure water, this is estimated.sup.1 to require a pressure of 48 megabar, which is beyond current experimental capabilities and may only exist in the interior of large planets or stars.sup.2-4. Indeed, recent estimates and experiments indicate that water at pressures accessible in the laboratory will at best be superionic with high protonic conductivity.sup.5, but not metallic with conductive electrons.sup.1. Here we show that a metallic water solution can be prepared by massive doping with electrons upon reacting water with alkali metals. Although analogous metallic solutions of liquid ammonia with high concentrations of solvated electrons have long been known and characterized.sup.6-9, the explosive interaction between alkali metals and water.sup.10,11 has so far only permitted the preparation of aqueous solutions with low, submetallic electron concentrations.sup.12-14. We found that the explosive behaviour of the water-alkali metal reaction can be suppressed by adsorbing water vapour at a low pressure of about 10.sup.-4 millibar onto liquid sodium-potassium alloy drops ejected into a vacuum chamber. This set-up leads to the formation of a transient gold-coloured layer of a metallic water solution covering the metal alloy drops. The metallic character of this layer, doped with around 5 × 10.sup.21 electrons per cubic centimetre, is confirmed using optical reflection and synchrotron X-ray photoelectron spectroscopies. Spectroscopic measurements confirm that when water is adsorbed on drops of an alkali alloy at low pressure a gold-coloured metallic layer forms as electrons rapidly move from the drop into the water., Author(s): Philip E. Mason [sup.1] , H. Christian Schewe [sup.1] [sup.2] , Tillmann Buttersack [sup.1] [sup.2] [sup.3] , Vojtech Kostal [sup.1] , Marco Vitek [sup.1] , Ryan S. McMullen [sup.3] [...]

The reaction of diorganotin(IV) oxides, [R.sub.2]SnO with R = n-butyl and t-butyl, with nitric acid in different stoichiometric ratios resulted in the formation of different products depending on the organic groups attached to the tin atom: the diorganotin(IV) dinitrate dihydrates, n-[Bu.sub.2]Sn[(N[O.sub.3]).sub.2] x 2[H.sub.2]O (2d) and t-[Bu.sub.2]Sn[(N[O.sub.3]).sub.2] x 2[H.sub.2]O (2e), the mixed diorganotin(IV) nitrate methoxide oxide n-[Bu.sub.2]Sn(N[O.sub.3]) (n-[Bu.sub.2]SnOMe)O (6), and the diorganotin(IV) nitrate hydroxide hydrate t-[Bu.sub.2]Sn(N[O.sub.3])(OH)-[H.sub.2]O = [t-[Bu.sub.2]Sn(OH)([H.sub.2]O)][N[O.sub.3]] (7). On examination of the solubility of the primary reaction products in different solvents, the three additional compounds t-[Bu.sub.2]Sn(N[O.sub.3])(OH) x DMSO (8), t-[Bu.sub.2]Sn(N[O.sub.3])(OH) x THF, and 2-t-[Bu.sub.2]Sn(N[O.sub.3])(OH) x DMF = [[t-[Bu.sub.2]Sn(OH)dmf].sub.2][[N[O.sub.3]].sub.2] x[[t-[Bu.sub.2]Sn(N[O.sub.3])OH].sub.2] (9) could be isolated. All compounds have been structurally characterized by single crystal X-ray diffraction (primary results for 7) with special attention paid to dimensionality (2d and 2c = monomeric, hydrogen bonded molecules; 6 = dimeric molecules of ladder-type structure; 7 = dimeric cation; 8 = dimeric molecule with hydrogen bonded solvent molecules; 9 = both components dimeric), tin coordination (6, 7, 8, and 9 = trigonal bipyramidal; 2d and 2e = eightfold), and nitrate bonding modes (7 and 9 = isolated, hydrogen bonded; 6, 8, and 9 (component 2) = monodentate; 2d and 2e = symmetrical bidentate), the latter one being analyzed using both Sn-O and N-O distances. Key words: diorganotin(IV) compounds, nitrates, tetraorganodistannoxanes, hydrates, structure types, structure determination, coordination behaviour. La reaction des oxydes de diorganoetain(IV), de formule [R.sub.2]SnO (ou R = n-Butyl et t-Butyl), avec l'acide nitrique, dans diverses proportions strechiometriques a conduit a la formation de differents produits dont la nature dependait des groupes organiques lies a l'atome d'etain : les dinitrates de diorganetain(IV) dihydrates, n[Bu.sub.2]Sn[(N[O.sub.3]).sub.2] x 2[H.sub.2]O (2d) et t[Bu.sub.2]Sn[(N[O.sub.3]).sub.2] x 2[H.sub.2]O (2e), le compose mixte d'oxyde methanolate de diorganoetain(IV) et nitrate de diorganoetain(IV), n[Bu.sub.2]Sn(N[O.sub.3])(n[Bu.sub.2]SnOMe)O (6) et l'hydroxyde nitrate de diorganoetain(IV) hydrate, t[Bu.sub.2]Sn(N[O.sub.3])(OH)-[H.sub.2]O = [t[Bu.sub.2]Sn(OH)([H.sub.2]O)][N[O.sub.3]] (7). Apres examen de la solubilite des produits primaires de reaction dans differents solvants, trois autres composes ont pu etre isoles : t[Bu.sub.2]Sn(N[O.sub.3])(OH) x DMSO (8), t[Bu.sub.2]Sn(N[O.sub.3])(OH) x THF et 2t[Bu.sub.2]Sn(N[O.sub.3])(OH)-DMF = [t[Bu.sub.2]Sn(OH)dmf]2[[N[O.sub.3]].sub.2] x[[t[Bu.sub.2]Sn(N[O.sub.3])OH].sub.2] (9). La structure de ces composes aete determinee par cristallographie aux rayons X (premiers resultats obtenus pour 7), en particulier la dimensionnalite (2d et 2c = molecules monomeriques a liaisons hydrogenes, 6 = molecules dimeriques de structure en echelle; 7 = cation dimerique, 8 = molecule dimerique associeea des molecules de solvant a liaisons hydrogene; 9 = deux composants dimeriques), la coordination de l'etain (6, 7, 8, 9 = trigonalebipyramidale; 2d, 2e = ti huit plis) et les modes de liaisons du nitrate (7, 9 = isole, a liaisons hydrogene; monodentate, avec les composants dimeriques 6, 8 et 9; bidentate symetrique, avec 2d et 2e), le compose 9 ayant ete analyse a l'aide des longueurs des liaisons Sn-O et N-O. [Traduit par la Redaction] Mots-cles : diorganoetains(IV), nitrates, tetraorganodistannoxanes, hydrates, types de structure, determination de la structure, comportement de coordination., Introduction Nitrates with diorganotin(IV) moieties [R.sub.2]Sn belong to the longest known compounds in organotin(IV) chemistry, (1,2) prepared by the reaction of diorganotin(IV) oxides with nitric acid. When the silver nitrate [...]

The reaction of diorganotin(IV) oxides, [R.sub.2]SnO with R = Me, Et, and i-Pr, with nitric acid in different stoichiometric ratios resulted in the formation of different products depending on the organic groups. The diorganotin(IV) nitrate hydroxides [Me.sub.2]Sn(N[O.sub.3])(OH) (1a) [Et.sub.2]Sn(N[O.sub.3])(OH), α-1b, β-1b, i-[Pr.sub.2]Sn(N[O.sub.3])(OH) (1c), the diisopropyltin(IV) dinitrate dihydrate, i-[Pr.sub.2]Sn[(N[O.sub.3]).sub.2] x 2[H.sub.2]O (2c) and the diisopropyltin(IV) nitrate oxalate dihydrate, [[i-[Pr.sub.2]Sn(N[O.sub.3])].sub.2]Ox x 2[H.sub.2]O (3) as side-product. On examination of the solubility of the primary reaction products in different solvents, the two additional compounds [Me.sub.2]Sn(N[O.sub.3])(OH)-DMSO (4) and 2i-[Pr.sub.2]Sn[(N[O.sub.3]).sub.2] x 3DMSO = [i-[Pr.sub.2]Sn(N[O.sub.3])[(dmso).sub.3]] [i-[Pr.sub.2]Sn[(N[O.sub.3]).sub.3]] (5) have been isolated. All compounds have been structurally characterized by single crystal X-ray diffraction with special respect to dimensionality (1a, α-1b, 1c = dimeric molecules hydrogen bonded to one-dimensional chains; β-1b = two-dimensional coordination polymer; 2c = monomeric; 3 = monomeric, tin atoms linked via a double side-on chelating oxalate ion; 4 = dimeric, 5 = monomeric anion/cation), tin coordination (trigonalbipyramidal = 1a, α-1b, 1c; six-fold = β-1b; seven-fold = 3, 4, 5-cation; eight-fold = 2c, 5-anion) and nitrate bonding modes (monodentate = 1a, α-1b, 1c; unsymmetrical bidentate = 3, symmetrical bidentate = 3, 4, 5-cation, 5-anion; syn-anti bridging = P-1b), the latter one being analysed using both, Sn-O and N-O distances. Key words: diorganotin(IV) compounds, nitrates, oxalates, hydrates, structure types, structure determination, coordination behavior. La reaction des oxydes de diorganoetain(IV) oxides, [R.sub.2]SnO (ou R=Me, Et et i-Pr), avec l'acide numeriques dans diverses proportions strechiometriques a conduit a la formation de differents produits dont la nature dependait des groupes organiques: les hydroxydes nitrate de diorganoetain(IV), de formules [Me.sub.2]Sn(N[O.sub.3])(OH) (1a), [Et.sub.2]Sn(N[O.sub.3])(OH) (α-1b et α-1b) et i-[Pr.sub.2]Sn(N[O.sub.3])(OH) (1c), le dinitrate de diisopropyletain(IV) dihydrate, i-[Pr.sub.2]Sn[(N[O.sub.3]).sub.2] x 2[H.sub.2]O (2c), et un sous-produit, l'oxalate nitrate de diisopropyletain(IV) dihydrate, [[i-[Pr.sub.2]Sn(N[O.sub.3])].sub.2]Ox x 2[H.sub.2]O (3). Apres examen de la solubilite des produits primaires de reaction dans differents solvants, deux autres composes ont ete isoles: [Me.sub.2]Sn(N[O.sub.3])(OH)-DMSO (4) et 2i-[Pr.sub.2]Sn[(N[O.sub.3]).sub.2] x 3DMSO = [i-[Pr.sub.2]Sn(N[O.sub.3])[(dmso).sub.3]] [i-[Pr.sub.2]Sn[(N[O.sub.3]).sub.3]] (5). La structure de ces composes a ete determinee par cristallographie aux rayons X, en particulier la dimensionnalite (1a, α-1b, 1c = molecules dimeriques reliees par liaisons hydrogene a des chaines unidimensionnelles; α-1b = polymere de coordination bidimensionnel; 2c = monomere; 3 = monomere; atomes d'etain relies par l'intermediaire d'un ion double lateral d'oxalate chelateur; 4 = dimere, 5 = anion ou cation monomerique), coordination de l'etain (trigonale-bipyramidale, avec 1a, α-1b, 1c; a six plis, avec α-1b; a sept plis, avec 3, 4 et le cation 5; a huit plis, avec 2c et l'anion 5) et les modes de liaisons du nitrate (monodentate, avec 1a, α-1b et 1c; bidentate asymetrique, avec 3, bidentate symetrique, avec 3,4, le cation 5 et l'anion 5; syn-anti, avec α-1b), le compose 5 ayant ete analyse a l'aide des longueurs des liaisons Sn-O et N-O. [Traduit par la Redaction] Mots-cles : diorganoetains(IV), nitrates, oxalates, hydrates, types de structure, determination de la structure, comportement de coordination., Introduction In the past, a tremendous number of different diorganotin(IV) compounds, [R.sub.2]Sn, with nitrates have been synthesized. They have been known since the beginning of organotin chemistry, when Lowig, (1) [...]