Fe-Ni invar alloy: an example of fractal decomposition?

The important experimental results of irradiated and unirradiated Ni-Fe alloys and some approaches to explain the various contradictory behaviours are discussed. We outline the known results of the scattering experiments and suggest possible directions for theoretical investigations to explain the decomposition kinetics of the FeNi Invar alloy.Обговорюються важливі експериментальні результати опромінених та не опромінених NiFe-сплавів, а також деякі апроксимації для пояснення різних суперечливих характеристик. Ми підкреслюємо відомі результати, отримані в експериментах з розсіянням, та пропонуємо можливі напрямки для теоретичних досліджень, щоб пояснити кінетику розкладу FeNi ИНВАР сплава.Обсуждаются важные экспериментальные результаты облученных и необлученных Ni-Fe-сплавов, а также некоторые аппроксимации для объяснения различных противоречивых характеристик. Мы подчеркиваем известные результаты, полученные в экспериментах с рассеянием, и предлагаем возможные направления для теоретических исследований, чтобы объяснить кинетики разложения FeNi ИНВАР сплава

Temperature controlled martensitic phase transformations in a model NiAl alloy

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Structural and chiroptical analysis of naturally occurring (-)-strychnine.

Structural aspects such as chemical exchange, dimerization, solvent association, nitrogen inversion and protonation status of strychnine were investigated using experimental and calculated data. The information was mainly interpreted in view of a successful determination of the absolute configuration (AC) with strychnine (base and salt) as test molecule due to its importance in chemistry. By geometry optimization a stable isomer of protonated strychnine was found with an inverted nitrogen, however, 25 kcal/mol higher in energy. It is shown that solvent association can be assumed in protic solvents such as methanol and dimerization to a small extent in polar/protic solvents. However, the monomeric structural model neglecting explicit solvent molecules still allows the correct prediction of the AC of base and hydrochloride using optical rotation and ECD data

Hidden flexibility of strychnine.

The prototypic molecule for conformational rigidity, that is, strychnine, exhibits fast conformational exchange on the NMR timescale at room temperature. A comprehensive description of this up-to-now-hidden stereodynamic behavior is presented, which combines experimental and computational data