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•Solvatochromism of ligand-to-metal charge-transfer excited states is discussed.•The change in dipole moment can be obtained with the Lippert-Mataga methodology.•Quantum-chemical ...calculations complement the Lippert-Mataga experimental study.
We report a systematic experimental and quantum-chemical study of electric dipole moments of a metal complex, dissolved in organic media, in the ground and electronically-excited states. Electric dipole moments of a model organometallic complex in the ground and emissive states and the difference thereof were analyzed applying simplified Lippert-Mataga methodology and calculations at different levels of density functional theory (B3LYP/DGDZVP, B3LYP/3-21G*, B3LYP/6-31G**, B3LYP/6-311G**, B3LYP/SDD, and B3LYP/cep-121G). The contribution provides the experimental systematic estimation of the change in electric dipole moments of an organometallic solute based on the changes in transition energies induced by systematic variations in the solvent, while the quantum-chemical data complement and detail the spectral results. With the Lippert-Mataga methodology, the existence of general and, to a lesser extent, specific solvent effects was evidenced. The systematic study shed more light on the solvatochromism of organometallic compounds.
The article presents the concept of the control intellectualization for the waveguide paths induction soldering process. This is a concept of the intelligent information system designed to support ...decision-making in control the technological process of creating permanent connections using induction heating in conditions of incomplete or unreliable information. The system should implement methods for assessing the reliability of information on process parameters, methods for estimating the magnitude of measuring tools errors and compensation methods for obtaining unreliable information, as well as methods for predicting the development of the technological process based on the analytical core of the expert system to generate a control action when measuring devices fail. The implementation of this concept will make it possible to recognize interference with measuring instruments and their failure for the further formation of sustainable process control of induction soldering.
The article presents a mathematical model of pipe heating in the process of induction brazing of waveguide paths. The object of research is the technological process of induction brazing, in ...particular, the regularities of energy distribution over time over the volume of the pipe Assembly of the waveguide path. The purpose of creating the model is to improve the quality of control of the production process of waveguide paths based on induction heating. The presented models will be actively used in the development of an algorithm for adaptive (intelligent) control of the technological process of induction heating of waveguide path assemblies in order to achieve uniform heating of the brazed elements to form a high-quality one-piece connection.
The tribological properties of the “copper alloy–carboxylic acid‒steel” system are studied. It is found that the wear-free mode accompanied by an increase in the pH of lubricant solutions, a decrease ...in the electrical conductivity, and a variation in the friction-surface charge is implemented in the “copper alloy–valeric acid–steel” and “copper alloy–caproic acid–steel” tribosystems. With the help of quantum-chemical calculations via the UB3LYP/Lanl2DZ method, it is demonstrated that the total charge of a metal cluster, the local distribution of electron and spin densities at copper atoms, and the structure of hydrocarbon radicals of carboxylic acids affect the physicochemical properties of the system during the formation of servovite films.
In this article, a comparative analysis of the existing software was carried out, a description of the subject area of the developed system was given, existing software tools, such integrated ...development environments as Xcode, Xamarin, FireMonkey were analyzed. As a result of the work, software was developed that made it possible to obtain experiment data, edit and delete experiments, change the parameters of the installations leading to emergencies and lead to the installation of induction soldering automation systems remotely and internally in the existing information infrastructure.
Modern quantum-chemical methods have been used to model and assign the bands of the electronic spectrum in the near UV–visible region of a structurally intricate metal complex with organometallic σ ...and π bonds. The properties of the frontier and nearest molecular orbitals and the nature of the electronic transitions with ligand-to-metal charge transfer have been estimated.
Modern quantum-chemical and photophysical methods have been used to study the structure of the frontier molecular orbitals and the nature of ligand-to-metal charge transfer (LMCT) transitions of ...structurally complex d0-metallocenes. It has been shown that such metal complexes with carboranyl ligands have emissive LMCT states with preferential charge transfer from aromatic π-ligands to the metal and a large electric dipole moment. The electronic excitation and absorption spectra were simulated for the first time, and dipole moments of metal complexes containing metal–carbon σ- and π-bonds were estimated, which is of fundamental importance for the development of molecular photonics.
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