Publications by authors named "G Espinosa-Perez"

A conformational study has been performed for galphimines A and B, which differ from each other only in an acetate moiety on ring B of galphimine A. Mechanical molecular calculations showed that the predominant conformers in a Boltzman distribution are those which establish an intramolecular hydrogen bond between the hydroxyls on rings A and B, keeping a similar conformation on the rest of the molecule. The existence of these conformers was confirmed by NMR spectroscopy in (D6) DMSO solution.

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On the basis of the data obtained by X-ray diffraction, the properties of two independent crystallographic subsystems in the [Fe(tpen)](ClO4)2.2/3H2O complex are studied in detail with the density functional method B3LYP. The energies of singlet, triplet, and quintet states at different temperatures are obtained, the influences of geometry on energy changes are analyzed, the regularity of the spin-state interconversions is investigated, and the effect of the triplet and action of the anion on spin crossover are discussed.

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The tetraphenylimidodiphosphinate [N-(P,P-diphenylphosphinoyl)-P,P-diphenylphosphinimidate] ion forms stable tris-chelates with the Bi(III), In(III), and Ga(III) cations. The crystal and molecular structures of [M{(OPPh(2))(2)N}(3)] (M = Ga, In, Bi) were determined by X-ray diffractometry. The geometry around the bismuth atom in compound 3 displays an approximately C(3)(v)() symmetry.

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