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The iron(III) complexes [Fe(H2O)n(OH)m]3−m (n + m = 5, 6, m ≤ 3) and corresponding proton transfer reactions are studied with total energy calculations, the nudged elastic band (NEB) method, and molecular dynamics (MD) simulations using ab initio and a modification of reactive force field potentials, the ReaxFF-AQ potentials, based on the implementation according to Böhm et al. [J. Phys. Chem. C 120, 10849–10856 (2016)]. Applying ab initio potentials, the energies for the reactions [Fe(H2O)n(OH)m]3−m + H2O → [Fe(H2O)n−1(OH)m+1]2−m + H3O+ in a gaseous environment are in good agreement with comparable theoretical results. In an aqueous (aq) or alkaline environment, with the aid of NEB computations, respective minimum energy paths with energy barriers of up to 14.6 kcal/mol and a collective transfer of protons are modeled. Within MD simulations at room temperature, a permanent transfer of protons around the iron(III) ion is observed. The information gained concerning the geometrical and energetic properties of water and the [Fe(H2O)n(OH)m]3−m complexes from the ab initio computations has been used as reference data to optimize parameters for the O–H–Fe interaction within the ReaxFF-AQ approach. For the optimized ReaxFF-AQ parameter set, the statistical properties of the basic water model, such as the radial distribution functions and the proton hopping functions, are evaluated. For the [Fe(H2O)n(OH)m]3−m complexes, it was found that while geometrical and energetic properties are in good agreement with the ab initio data for gaseous environment, the statistical properties as obtained from the MD simulations are only partly in accordance with the ab initio results for the iron(III) complexes in aqueous or alkaline environments. [ABSTRACT FROM AUTHOR]

People in a changing environment must decide between exploiting options they currently favor and exploring alternative options that provide additional information about the state of the environment. For example, drivers must decide between purchasing gas at their currently favored station (i.e., exploit) or risk a fruitless trip to another station to evaluate whether the price has been lowered since the last visit. Previous laboratory studies on exploratory choice have found that people choose strategically and explore alternative options when it is more likely that the relative value of competing options has changed. Our study extends this work by considering how global trends (which affect all options equally) influence exploratory choice. For example, during an economic crisis, global gas prices may increase or decrease at all stations, yet consumers should still explore strategically to find the best option. Our research question is whether people can maintain effective exploration strategies in the presence of global trends that are irrelevant in that they do not affect the relative value of choice options. We find that people explore effectively irrespective of global trends.