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Updated: May 30, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Integrated NMR and computational study of push-pull NLO probes: interplay of solvent and structural effects
Alberto Marini1, Sara Macchi, Sandro Jurinovich
1Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126, Pisa Italy.
Abstract:
In this study we combined QM calculations and NMR measurements to understand at a detailed level the complex interplay of structural/electronic properties with the effects of the solvent in the NLO activity of push-pull systems, quantified in terms of variations of the static hyperpolarizability. Different parameters (bond lengths and bond length alternation, vibrational frequencies, electronic charge distribution) are introduced and tested to rationalize both the solvent sensitivity of three molecular systems (namely, p-nitroaniline, ethyl 4-ammino benzoate, and 5-nitro-1H-indole) and the differences among them. This analysis has finally allowed us to establish a clear correlation between the charge transfer behavior of the systems, their NLO properties, and NMR parameters also validating simplified but effective chemical analyses based on resonance limit forms.
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