The peculiarities of spin effects in photoinduced electron transfer (ET) in diastereomers of donor-acceptor dyads are considered in order to study the influence of chirality on reactivity. Thus, the spin selectivity—the difference between the enhancement coefficients of chemically induced dynamic nuclear polarization (CIDNP)—of the dyad’s diastereomers reflects the difference in the spin density distribution in its paramagnetic precursors that appears upon UV irradiation. In addition, the CIDNP coefficient itself has demonstrated a high sensitivity to the change of chiral centers: when one center is changed, the hyperpolarization of all polarized nuclei of the molecule is affected. The article analyzes the experimental values of spin selectivity based on CIDNP calculations and molecular dynamic modeling data in order to reveal the effect of optical configuration on the structure and reactivity of diastereomers. In this way, we succeeded in tracing the differences in dyads with L- and D-tryptophan as an electron donor. Since the replacement of L-amino acid with D-analog in specific proteins is believed to be the cause of Alzheimer’s and Parkinson’s diseases, spin effects and molecular dynamic simulation in model dyads can be a useful tool for investigating the nature of this phenomenon.

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In this paper, we propose a computational scheme for the theoretical estimation of gas‐phase acidity of uracil and its derivatives. The calculation of the acidities (рKа) of the compounds under study was performed using quantum chemical calculations with the composite G3MP2B3 method. The solvent effect was taken into account within the polarizable continuum model and density functional theory calculations by the Polarizable continuum model (solvate model density) ‐ the exchange functional of Tao, Perdew, Staroverov, and Scuseria method. We evaluated the influence of the nonspecific solvation using two approaches (single‐point calculations versus full optimization of the studied structures) and found that the use of full optimization of the geometry of the compound for calculating the solvent effect significantly enhances the accuracy of numerical estimation of the рKа values. The mean absolute deviation decreases by 0.60 and 0.37 units of рKа in the case of the single‐point and full‐optimization approaches, respectively. The most pronounced advantage of the latter approach is its universality. Indeed, because of the implicit accounting of solvation, this computational scheme may be applied to the calculations of the рKа values of any class of compounds without reservations. The proposed computational scheme for the estimation of acidity opens new opportunities for further studies in the field of acidity.

The electrolyte is an important component of lithium-ion batteries, especially when it comes to cycling high-voltage cathode materials. In this paper, we propose an algorithm for estimating both the oxidising and reducing potential of electrolytes using molecular dynamics and quantum chemistry techniques. This algorithm can help to determine the composition and structure of the solvate complexes formed when a salt is dissolved in a mixture of solvents. To develop and confirm the efficiency of the algorithm, LiBF4 solutions in binary mixtures of ethylene carbonate (EC)/dimethyl carbonate (DMC) and sulfolane (SL)/dimethyl carbonate (DMC) were studied. The structure and composition of the complexes formed in these systems were determined according to molecular dynamics. Quantum chemical estimation of the thermodynamic and oxidative stability of solvate complexes made it possible to establish which complexes make the most significant contribution to the electrochemical stability of the electrolyte system. This method can also be used to determine the additive value of the oxidation and reduction potentials of the electrolyte, along with the contribution of each complex to the overall stability of the electrolyte. Theoretical calculations were confirmed experimentally in the course of studying electrolytes by step-by-step polarisation using inert electrodes. Thus, the main aim of the study is to demonstrate the possibility of using the developed algorithm to select the optimal composition and solvent ratio to achieve predicted redox stability.