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The dynamics of a molecule in a magnetic field is significantly different from its zero-field counterpart. One important difference in the presence of a field is the Lorentz force acting on the nuclei, which can be decomposed as the sum of the bare nuclear Lorentz force and a screening force due to the electrons. This screening force is calculated from the Berry curvature and can change the dynamics qualitatively. It is therefore important to include the contributions from the Berry curvature in molecular dynamics simulations in a magnetic field. In this work, we present a scheme for calculating the Berry curvature numerically using a finite-difference technique, addressing challenges related to the arbitrary global phase of the wave function. The Berry curvature is calculated as a function of bond distance for H2 at the restricted and unrestricted Hartree–Fock levels of theory and for CH+ as a function of the magnetic field strength at the restricted Hartree–Fock level of theory. The calculations are carried out using basis sets of contracted Gaussian functions equipped with London phase factors (London orbitals) to ensure gauge-origin invariance. In this paper, we also interpret the Berry curvature in terms of atomic charges and discuss its convergence in basis sets with and without London phase factors. The calculation of the Berry curvature allows for its inclusion in ab initio molecular dynamics simulations in a magnetic field. [ABSTRACT FROM AUTHOR]

[Display omitted] • New hydrogels of the bio-composites type based on ClAETA and CNF. • CNF favors the adsorption of bio-composites. • P(ClAETA)1-12-2%CNF removes 43.09 mg g−1 of NFX with an efficiency of 70% • Bio-composites are effective and reusable adsorbents in adsorption-desorption cycles. • Computational study allows to identify the main intermolecular interactions. In the present work, new biocomposite hydrogels were prepared based on the vinyl monomer 2-methacroyloxyethyltrimethyl ammonium chloride (ClAETA) in the presence of nanofibrillated cellulose (CNF) for the removal of the emerging contaminant nafcillin sodium monohydrate (NFX). The hydrogels were synthesized via free radicals, with the amount of CNF varied, and characterized by fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), and scanning electron microscope (SEM) techniques. The capacity to absorb water and to remove NFX was determined through batch studies. It was observed that the presence of CNF significantly promotes both properties, with a hydration capacity of 2100% and an NFX adsorption capacity of 45 mg g−1 in P(ClAETA)1-12-2%CNF (pH 6, 0.01 g of adsorbent, initial concentration of NFX 200 mg g−1). The conformational study showed that in the most stable conformation, CNF avoids direct interaction with the NFX molecule. Herein, the main interactions are predominantly dominated by weak interactions such as London dispersion and electrostatic interactions between charged groups. Molecular dynamics simulations distinguish the existence of π-π stacking interactions between aromatic rings from NFX in the polymer + NFX system. Contact interactions were qualitatively and quantitatively characterized by the NCI index and the IGM analysis. [ABSTRACT FROM AUTHOR]