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Large aqueous ions are interesting because they are useful in materials science (for example to generate thin films) but also because they serve as molecular models for the oxide-aqueous mineral interface where spectroscopy is difficult. Here we show that new clusters of the type M[(μ-OH)2 Co(NH3 )4 ]3 (NO3 )6 (M=Al, Ga) can be synthesized using Werner's century-old cluster as a substitutable framework. We substituted Group 13 metals into the hexol Co[(μ-OH)2 Co(NH3 )4 ]36+ ion to make diamagnetic heterometallic ions. The solid-state structure of the hexol-type derivatives were determined by single-crystal XRD and NMR spectroscopy and confirmed that the solid-state structure persists in solution after dissolution into either D2 O or [D6 ]DMSO. Other compositions besides these diamagnetic ions can undoubtedly be made using a similar approach, which considerably expands the number of stable aqueous heteronuclear ions.

Who benefits when economic costs to the pursuit of higher education are diminished? Can such reforms advance the educational trajectory of historically marginalized groups, including women and indigenous people, or are historic social inequalities replicated in the use of new opportunities? The 2016 Ley de Gratuidad in Chile presents a unique opportunity to examine who benefits and how when the state provides a policy guaranteeing free higher education at participating universities. Given the systematic biases and cultural norms faced by women and indigenous people in Chile and the broad design of the state-led policy, the educational reform constitutes an important test of the extent to which lowering costs can facilitate education across an economically and socially diverse population. Leveraging data from two waves of a household survey, this paper finds that educational attainment, measured in the number of years of schooling achieved by respondents, is significantly higher for those who receive such a benefit, consistent with the design and intent of the policy. More surprisingly, these increases in years of education occur for women and indigenous people, even though no programmatic element emphasizes these groups. The results suggest that state financing is significantly associated with promoting higher education in the population and that women, the poor, and indigenous people are significant beneficiaries of this effect despite the social and cultural barriers in the country. [ABSTRACT FROM AUTHOR]

In this paper, we seek to draw lessons about the roles that religious institutions can play in promoting democracy in deeply divided societies by examining the experience of the Catholic Church in Latin America. We focus on the cases of Chile and El Salvador, two countries where the Catholic Church played a decisive role in advancing democracy after autocratic military rule. These two cases illustrate where theology and action productively promoted social change in highly conflictual societies. We note challenges to democracy in the region, but also new opportunities in the era of the first Latin American pope, Francis. [ABSTRACT FROM AUTHOR]

Flat-[Ga13(μ3-OH)6(μ-OH)18(H2O)24](NO3)15 (Ga13) and heterometallic [Ga13−xInx(μ3-OH)6(μ-OH)18(H2O)24](NO3)15 (x = 5, 4) clusters were synthesized by the electrolysis of metal nitrate salt solutions to directly form, without purification, aqueous precursor inks for InxGa13−xOy semiconducting films in <2 h. Raman spectroscopy and 1H-NMR spectroscopy confirm the presence of [Ga13−xInx(μ3-OH)6(μ-OH)18(H2O)24(NO3)15] clusters. Bottom-gate thin-film transistors were fabricated using ∼15 nm-thick Ga13−xInxOy films as the active channel layer, displaying turn-on voltages of −2 V, and on/off current ratios greater than 106. The average channel mobility of the transistors fabricated from the cluster solutions generated by electrolysis was ∼5 cm−2 V−1s−1 which was more than twice that of transistors fabricated from control solutions with the simple nitrate salt precursors of ∼2 cm−2 V−1s−1. Electrochemical cluster synthesis thus provides a simple and direct route to aqueous precursors for solution-processed inorganic electronics. [ABSTRACT FROM AUTHOR]

What explains the recent rise in non-contributory social insurance programmes in Latin America? Since the 1990s, Latin American countries have enacted significant social policy reforms that have supplemented contributory insurance policies with new or expanded non-contributory programmes, financed by general tax revenues. We present a political explanation for this phenomenon, arguing that the process of deindustrialization, and especially the increased labour insecurity that it entails, has changed the mix of social insurance policies favoured by different individuals in the income and employment distributions. A long-term increase in economic insecurity has increased the relative demand for tax-financed, rather than contribution-financed, social insurance. Elected officials, especially those in the recent ‘rise of the Left’ in Latin America, have proved eager to meet these demands. We find strong evidence for this argument using both cross-national data on non-contributory pension policy adoption and individual-level data on policy preferences. [ABSTRACT FROM PUBLISHER]

Large aqueous ions are interesting because they are useful in materials science (for example to generate thin films) but also because they serve as molecular models for the oxide-aqueous mineral interface where spectroscopy is difficult. Here we show that new clusters of the type M[(μ-OH) 2 Co(NH 3 ) 4 ] 3 (NO 3 ) 6 (M=Al, Ga) can be synthesized using Werner's century-old cluster as a substitutable framework. We substituted Group 13 metals into the hexol Co[(μ-OH) 2 Co(NH 3 ) 4 ] 3 6+ ion to make diamagnetic heterometallic ions. The solid-state structure of the hexol-type derivatives were determined by single-crystal XRD and NMR spectroscopy and confirmed that the solid-state structure persists in solution after dissolution into either D 2 O or [D 6 ]DMSO. Other compositions besides these diamagnetic ions can undoubtedly be made using a similar approach, which considerably expands the number of stable aqueous heteronuclear ions., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

NMR spectroscopy is the go-to technique for determining the solution structures of organic, organometallic, and even macromolecular species. However, structure determination of nanoscale aqueous inorganic clusters by NMR spectroscopy remains an unexplored territory. The few hydroxo-bridged inorganic species well characterized by 1 H Nuclear Magnetic Resonance spectroscopy ( 1 H-NMR) do not provide enough information for signal assignment and prediction of new samples. 1 H-NMR and quantum mechanical (QM) computations were used to characterize the NMR spectra of the entire array of inorganic flat- Ga 13- x In x (0 ≤ x ≤ 6) nanoscale clusters in solution. A brief review of the known signals for μ 2 -OH and μ 3 -OH bridges gives expected ranges for certain types of protons, but does not give enough information for exact peak assignment. Integration values and NOESY data were used to assign the peaks of several cluster species with simple 1 H-NMR spectra. Computations agree with these hydroxide signal assignments and allow for assignment of the complex spectra arising from the remaining cluster species. This work shows that 1 H-NMR spectroscopy provides a variety of information about the solution behavior of inorganic species previously thought to be inaccessible by NMR due to fast ligand and/or proton exchange in wet solvents.