Borates and borosilicates are potential candidates for the design and development of glass formulations with important industrial and technological applications. A major challenge that retards the pace of development of borate/borosilicate based glasses using predictive modeling is the lack of reliable computational models to predict the structure‐property relationships in these glasses over a wide compositional space. A major hindrance in this pursuit has been the complexity of boron‐oxygen bonding due to which it has been difficult to develop adequate B–O interatomic potentials. In this article, we have evaluated the performance of three B–O interatomic potential models recently developed by Bauchy et al [J. Non‐Cryst. Solids, 2018, 498, 294–304], Du et al [J. Am. Ceram. Soc. https://doi.org/10.1111/jace.16082] and Edèn et al [Phys. Chem. Chem. Phys., 2018, 20, 8192–8209] aiming to reproduce the short‐to‐medium range structures of sodium borosilicate glasses in the system 25 Na2O x B2O3 (75 − x) SiO2 (x = 0‐75 mol%). To evaluate the different force fields, we have computed at the density functional theory level the NMR parameters of 11B, 23Na, and 29Si of the models generated with the three potentials and the simulated MAS NMR spectra compared with the experimental counterparts. It was observed that the rigid ionic models proposed by Bauchy and Du can both reliably reproduce the partitioning between BO3 and BO4 species of the investigated glasses, along with the local environment around sodium in the glass structure. However, they do not accurately reproduce the second coordination sphere of silicon ions and the Si–O–T (T = Si, B) and B‐O‐T distribution angles in the investigated compositional space which strongly affect the NMR parameters and final spectral shape. On the other hand, the core‐shell parameterization model proposed by Edén underestimates the fraction of BO4 species of the glass with composition 25Na2O 18.4B2O3 56.6SiO2 but can accurately reproduce the shape of the 11B and 29Si MAS‐NMR spectra of the glasses investigations due to the narrower B–O–T and Si‐O‐T bond angle distributions. Finally, the effect of the number of boron atoms (also distinguishing the BO3 and BO4 units) in the second coordination sphere of the network former cations on the NMR parameters have been evaluated.

Transitioning beyond a trial-and-error based approach for the compositional design of next-generation borosilicate-based bioactive glasses requires a fundamental understanding of the underlying compositional and structural drivers controlling their degradation and ion release in vitro and in vivo. Accordingly, the present work combines magic-angle spinning (MAS) NMR techniques, MD simulations, and DFT calculations based on GIPAW and PAW algorithms, to build a comprehensive model describing the short-to-medium-range structure of potentially bioactive glasses in the Na 2 O−P 2 O 5 −B 2 O 3 −SiO 2 system over a broad compositional space. P 2 O 5 preferentially tends to attract network modifier species, thus resulting in a repolymerization of the silicate network and a restructuring of the borate component. 11 B{ 31 P} and 31 P{ 11 B} dipolar recoupling experiments suggest that the ability of glasses to incorporate P 2 O 5 without phase separation is related to the formation of P−O−B(IV) linkages integrated into the borosilicate glass network. An analogous approach is used for elucidating the local environments of the Na + network modifiers. This work, along with future studies aimed at elucidating composition−structure−solubility/bioactivity relationships, will lay the foundation for the development of quantitative structure−property relationship (QSPR) models, thus representing a leap forward in the design of functional borosilicate bioactive glasses with controlled ionic release behavior.

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In this work, we demonstrate the use of two-dimensional electronic spectroscopy (2DES) to study the mechanism and time scale of the femtosecond Stokes shift dynamics in molecules characterized by intramolecular charge transfer, such as distyryl-functionalized boron dipyrromethene (BODIPY) molecules. The obtained results demonstrate that 2DES allows clear and direct visualization of the phenomenon. The analysis of the 2D data in terms of 2D frequency–frequency decay associated maps provides indeed not only the time scale of the relaxation process but also the starting and the final point of the energy flow and the associated reorganization energy, identified by looking at the coordinates of a negative signature below the diagonal. The sensitivity of the 2DES technique to vibrational coherence dynamics also allowed the identification of a possible relaxation mechanism involving specific interaction between a vibrational mode of the dye and the solvent.

Silver-mediated base pairs applied to DNA represent a new biomacromolecular nanomaterial useful for generating nanodevices as ion sensors. Reported herein is a full quantum chemical study devoted to give further knowledge on the electronic and energetic properties of C-Ag-C and mixed C-Ag-A mismatched base pairs. The B3LYP functional in conjunction with the dispersion effects (D3) has been applied. Single-point calculations have been also performed by using the M06-L functional. The investigation of their behavior has been extended to the duplex DNA modeled by the (dC-Ag-dC)2 and (dC-Ag-dA)2 more complex systems. The solvent effect has been taken into account by the conductor-like screening model, COSMO. In the case of mixed C-Ag-A and (dC-Ag-dA)2 systems, both the Watson-Crick and Hoogsteen arrangements have been taken into account. Results show that for (dC-Ag-dA)2 systems, the binding energies are almost double that of the corresponding values of C-Ag-A ones.