Amidequats have attracted considerable attention in research; however, their surface activity remains largely unknown, and their potential as emulsifiers is still unexplored. In this work, series of novel surface-active amidequats based on ecofriendly caprylic acid were synthesized and their micellization behavior in water was explored systematically. The surface tension, wettability, foamability and stability, and measurements of melting and crystallization temperatures were employed to characterize the compounds. The functionalization of amidequats containing an alkoxymethyl substituent significantly enhances micellization properties compared to the structurally analogous anionic surfactant, sodium caprylate. Moreover, for optimized molecule geometries, electrical dipole moments were determined and correlated with surface activity. Experimental and theoretical studies indicate that amidequats with 12 carbon atoms in the alkyl chain exhibit the highest surface and foam-forming activity, making them promising emulsifiers. Due to this fact, oil-in-water (o/w) or water-in-oil (w/o) emulsions using the mentioned amidequat were prepared, and their rheological analysis, ζ potential, topography analysis, and particle size were studied. A detailed investigation of the surface properties of amidequats was undertaken to assess their potential application in the cleaning agent and cosmetic industries.

The spectroscopic, thermal, and electrical properties of polypyrrole-co-poly(pyrrole-3-carboxylic acid) doped with p-TSA (p-toluenesulfonate) and AQS (anthraquinone sulfonate) are investigated. The semiconductor-like electrical characteristics of the systems are demonstrated by the variation in electrical conductivity as a function of temperature. The properties of conductivity and dielectricity are investigated. The investigated copolymers demonstrate 3D conductivity and a constant carrier density near the Fermi energy. Polarons and bipolarons are charge carriers, as indicated by IR and Raman spectra. The number of charge carriers is increased by doping the polypyrrole-co-poly(pyrrole-3-carboxylic acid) copolymer. The molecular structure of the ionized oligomer and the doped ones is analyzed using the density functional theory (DFT) methods. The time-dependent density functional theory methods are employed to analyze the electron transitions of the copolymers under investigation.

1H-Imidazol-3-ium-2-hydroxybenzoate (imidazolium salicylate or SalImi) is an organic ionic crystal with a helical hydrogen-bonded network. Crystallographic structure and quantum theory of atoms in molecule calculations are used to analyse the helical structure parameters. The negative area and negative linear temperature expansion occur in the range from 300 to 180 K and 180 to 100 K, respectively. Hydrogen bonding coupling below 180 K is associated with the temperature change in crystal behaviour. The crystal displays negative linear compressibility in the a-direction. The negative temperature expansion and negative linear compressibility are described by the "helical" mechanism. X-ray diffraction and vibrational spectroscopy were used for the structural and macroscopic analysis. The paper presents an analysis of the crystalline structure in the temperature range from 100 to 300 K and pressures from atmospheric to 2.27 GPa. In addition, the vibrational structure was analysed using Raman and infrared spectroscopy in the temperature range from 5 to 300 K and pressures from atmospheric to 3.56 GPa.

The electrical and spectroscopic properties of new polypyrrole/derivative composites combined with graphene quantum dots (GQDs) were investigated. This paper presents the findings of a study focused on materials that hold potential applications in the production of supercapacitors. The morphology of the synthesized materials was examined using fluorescence techniques as well as scanning and transmission electron microscopy. The investigated composites contain regular nanoparticles with sizes ranging from 50 to 150 nm. Electrical properties were studied using Raman spectroscopy, impedance spectroscopy, and voltammetry. The composite material consisting of sGQDs and poly(pyrrole-3-carboxylic acid) (PPyMCA/sGQDs) exhibits the highest specific capacitance of 215 (F g- 1) at 10 mV/s, which is reduced by 16 % when the sweep rate changes from 10 to 200 mV/s. The results demonstrate that it has the highest specific capacitance among the investigated composites and the least variation in value. The specific capacitance values can be attributed to the system's COOH groups and hydrogen bonds, suggesting that specific capacitance increases with a higher content of COOH groups. Moreover, the increased carboxyl groups reduce variations in specific capacitance with respect to the voltage sweep rate. The electrochemical stability of the PPy and PPyMCA/sGQDs films was tested using multicyclic galvanostatic charge-discharge experiments. The PPyMCA/sGQDs composite electrode shows significantly better cycling stability than PPY. In the first 40 cycles, the capacitance retention slightly drops to about 91 % of the original value, then stabilizes and stays nearly constant at around 190 F g- 1.

We showed that high pressure changes the number of polarons and bipolarons in a conducting copolymer, affecting its electrical properties.

The spectroscopic and electrical properties of poly(pyrrole-3-carboxylic acid) doped with p-TSA- (p-toluenesul- fonate) and AQS- (anthraquinone sulfonate) were investigated. The variation in electrical conductivity as a function of temperature shows that the systems have semiconductor -like electrical characteristics. The investigated polymers exhibit 3D conductivity and less than 0.6 eV energy gaps. The IR and Raman spectra show that the charge carriers are polarons and bipolarons. Doping the poly(pyrrole-3-carboxylic acid) increases the number of charge carriers. Electron paramagnetic resonance has shown that localized polarons and bipolarons are formed within these polymers.

In this article, we have reported the most recent results of our systematic studies of phenyl-ring substituent effect on proton tautomerism and stereoisomerism in 4-phenylamino-1,3-thiazol-2(5H)-one derivatives. The work concerns the synthesis, analysis of 1H and 13C NMR and FT-IR spectra, and X-ray crystal studies of three isomeric compounds, i.e. 5-dimethylaminomethylidene-4-(o-,m-,p-methoxyphenyl)amino-1,3-thiazol-2(5H)-ones. All three isomers were found to solely exist in the amino tautomeric form, both in the DMSO solution and the solid phase. In the molecules of all the title compounds, the o-,m-,p-methoxyphenylamine residue has synperiplanar disposition with respect to the thiazolone system, while the 5-dimethylaminomethylidene residue adopts the Z-configuration. DFT calculations correctly predict that the synperiplanar arrangement is favored in all investigated materials

Our study focuses on molecular rotors with fast-moving rotators and their potential applications in the development of new amphidynamic crystals. Steroidal molecular rotors with a dipolar fluorine-substituted phenyl group as the rotator were synthesized and characterized. Three different rotors were investigated with varying numbers of fluorine atoms. A comprehensive analysis was performed using vibrational spectroscopy (Raman, FT-IR), electronic circular dichroism (ECD), and dielectric response to understand the behavior of the investigated model rotors. The results were supported by theoretical calculations using Density Functional Theory (DFT) methods. The angle-dependent polarized Raman spectra confirmed the crystallinity of the samples. Nearly frequency and temperature-independent permittivity suggest low-frequency librational motion of stators. An in-depth analysis of ECD spectra revealed high conformational flexibility in solution, resulting in low ECD effects, while in the solid-state with restricted rotation, significant ECD effects were observed. These findings shed light on the conformational behavior and potential applications of the studied steroidal molecular rotors. Three different steroidal molecular rotors with a dipolar fluorine-substituted phenyl group rotator were synthesized. Raman and FT-IR measurements were used to analyse the effect of fluorine substitution on molecular dynamics of the phenyl ring. The electric properties were investigated with the impedance spectroscopy. ECD spectroscopy was used to approximate the solid-state structure of one of the rotors. image

We report a comprehensive characterization of the magnetic, electrical transport, Raman spectra, and thermal properties of the single-crystalline Zintl-type material EuIn2P2. The compound crystallizes with a hexagonal unit cell (space group P63/mmc) and orders magnetically at TC = 24 K with the Eu magnetic moments aligned ferromagnetically within the ab plane but tilted alternately along the c-axis direction. The effective and saturation magnetic moments agree with the theoretical values expected for the Eu2+ ion. For a range of several tens of kelvins above similar to 40 K, the electrical transport of EuIn2P2 is dominated by short-range magnetic interactions. The temperature dependence of the electrical resistivity was modeled in terms of variable-range hopping. Another indication of the latter scenario seems to be the observation, for EuIn2P2, of a quadratic dependence of the negative magnetoresistance on the magnetic field strength and the scaled magnetization. The temperature dependence of the Raman band position and FWHM, as well as the phonon lifetime, confirms the presence of the distinctive regions observed in transport and magnetic studies.

Efficient and subscribes to the principles of green chemistry synthesis of novel surface-active ionic liquids (SAILs) was characterized. Different surface properties and phytotoxicity were observed according to the structural variations of amphiphilic part of the SAILs. The analysis of the ATR infrared spectra revealed that the solute-solvent interactions are of the Van der Waals type, and the compounds studied are stable from 25 to 65 degrees C. The molecular and vibrational structures were analyzed using DFT methods. For optimized molecule geometries, electrical dipole moments were determined. The most significant contact angle values were observed for compounds with dipole moments greater than 20 Debye. The wettability of leaves surface was also investigated, and as a result, these SAILs were shown to be a potential candidate as effective crop protection agents.

The investigated symmetrical bis-adducts, i.e., bis(1-ethyl-4-hydroxy-2,2-dioxido-1H -2,1-benzothiazin-3-yl)(furan-2-yl/phenyl)methane and bis(4-hydroxy-2,2-dioxido-2H -1,2-benzoxathiin-3-yl)(furan-2-yl/4-methoxyphenyl)methane, essential objects for pharmacological studies, were found to exist in the liquid and solid phases in a double tautomeric enol form which allows the existence of acid-base interactions related to the proton transfer to the triethylamine and the formation of an intramolecular O-H middotmiddotmiddotO- hy-drogen bond between the intact OH group and the enolate O- atom. In the crystal lattice of triethylam-monium salts containing 1,2-benzoxathiine 2,2-dioxide moieties in the anion molecules, counter ions are connected by N-H middotmiddotmiddotO hydrogen bonds, in which the enolate O- atom plays the role of a proton accep-tor. Whereas in crystals with 2,1-benzothiazine 2,2-dioxide fragments in the anion molecules cation and anion molecules are linked by N-H middotmiddotmiddotO hydrogen bonds, in which the role of a proton acceptor is played by an O atom of a sulphonyl group that belongs to a bicyclic fragment which contains an enolate group. We have shown that the dipole-dipole interactions in the investigated ammonium salts may explain the orientation of the cationic N -H group once to the O- atom of the enolate group, another time to the O atom of the sulfonyl group. The effect of the structure of the anion molecule on the hydrogen bond-ing network in the crystals studied was analyzed by the X-ray diffraction method, the 1 H and 13 C NMR technique including COSY, NOESY, HSQC and HMBC two-dimensional patterns, and the Fourier transform infrared (FTIR) spectroscopy. Theoretical analysis of the interactions in the crystals was performed using Density Functional Theory (DFT) and Quantum Theory of Atoms in Molecules (QTAIM). (c) 2023 Elsevier B.V. All rights reserved.

New compounds of high pharmacological interest: 5-dimethylaminomethylidene-4-phenylamino-1,3-thiazol-2(5H)-one and 5-methoxycarbonylmethylidene-4-phenylamino-1,3-thiazol-2(5H)-one, were syn-thesized and investigated. Their crystal structure, chemical environment, and intermolecular interactions were studied by X-ray diffraction method and by NMR and FT-IR spectroscopy. The molecular interac-tions in the crystals were analyzed using Density Functional Theory (DFT), Quantum Theory of Atoms in Molecules (QTAIM), Hirshfeld surfaces, and fingerprint plots, with special emphasis on stereoisomerism and proton tautomerism. Both investigated compounds occur in the solution (DMSO) and in the solid state in the amine tautomeric form. The ylidene substituent with electron-donating effect only could sig-nificantly decrease the resonance effect of the carbonylimino group with the phenylamino moiety. In the molecules of both compounds, the phenylamino group has a synperiplanar conformation, and the yli-dene substituent has the Z configuration. The theoretical conformational analysis shows that the coplanar arrangement of the thiazolin-2-one and phenyl systems is preferred.(c) 2022 Published by Elsevier B.V.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

A negative linear temperature expansion and a negative linear compressibility were observed for imidazolium benzoate salt. Its strongly anisotropic strain induced by the temperature and pressure changes has been explained by the mechanism of H-bonded helices deformed in the structure. X-ray diffraction and vibrational spectroscopy were used to analyze interactions in the crystal. The Quantum Theory of Atoms in Molecules (QTAiM) approach was applied to analyze the hydrogen bonds and other interactions. In the salt under study, the interactions within the helix are substantially higher in energy than between helices. With decreasing temperature and increasing pressure, the value of the helix pitch increases while the value of the semi-major axis decreases, which results in the negative linear expansion and negative linear compression, respectively.

We reported a novel hydrated solid-state proton conductor's structure, charge transport, and spectroscopic properties. The resulting material of the hydrated imidazolium (ImiHemH(2)O) and pyrazolium (PyrHemH(2)O) hemimelitate is a solid-state hydrate with one water molecule per structural unit. The ions in the crystal structure are connected by N+-HO- hydrogen bonds and the anions are connected to the water molecules by O-HO hydrogen bonds. The strength of the intermolecular hydrogen bonds is important for the thermal and conductive properties of the studied hemimelitic acid salts. The chain motif of the N+-HO- hydrogen bonds influences the greater thermal stability of the salt. The weaker strength of the O-HO hydrogen bonds leads to better conductive properties of the salt.

5-[(Dimethylamino)methylidene]-4-{[3-(trifluoromethyl)phenyl]amino}-1,3-thiazol-2(5H)-one and the [4-(trifluoromethyl)phenyl]amino derivative, both C13H12F3N3OS, with the trifluoromethyl group substituted at the arene ring at the meta and para positions, were synthesized to study the structural changes associated with proton tautomerism of the amidine system. The studied compounds were found to be in the amine tautomeric form in both the solid and the liquid (dimethyl sulfoxide solutions) phase. In both isomers, the [(trifluoromethyl)phenyl]amino residue assumes a synperiplanar conformation with respect to the thiazolone system, while the 5-[(dimethylamino)methylidene] residue adopts the Z configuration. Density functional theory (DFT) calculations correctly predicted that the synperiplanar arrangement is favoured in both isomers. In the crystal, the whole independent molecule of the para compound is disordered over two alternative positions, with occupancy factors of 0.926 (3) and 0.074 (3).

Three new 5-dimethylaminomethylidene-4-phenylamino-1,3-thiazol-2(5H)-ones with an hydroxyl group in the ortho, meta and para positions on the phenyl ring were synthesized in order to deduce the structural changes occurring on prototropic tautomerism of the amidine system. The existence of all the title compounds solely in the amino tautomeric form has been established in the solid and liquid (dimethyl sulfoxide solution) phases. The title compounds are analyzed from the point of view of the electronic effects and conformational freedom of their molecules. The intermolecular interactions in the crystals and their supramolecular architecture are highlighted.

Electronic and vibrational structures of pyrrole oligomer and its derivatives were established on the basis of Density Functional Theory (DFT) and Time-dependent DFT (TD-DFT) computations. The influence of substituent groups on optical and electronic properties was investigated for polypyrrole and polypyrrole derivatives. Mo-lecular structure and frontier molecular orbitals of neutral and ionized oligomers were analyzed. The energy gap, ionization potential, electron affinity, electronegativity, and hardness were calculated and discussed.

An aqueous solution of sodium citrate stabilized gold nanoparticles (AuNP) in the presence of N-lauroyl-L-alanine (C12ALA) forms a stable gel. The structure of the gel and the distribution profile of AuNP in it were analyzed. Will nanoparticles separated from each other with sodium citrate behave in the same way in solution and trapped in the gel matrix? Will the spatial limitation of solvent molecules aggregate nanoparticles and destroy their homogeneity? These questions are very important from the point of view of the use of gold nanoparticles, trapped in the gel structure as carriers of drugs in the slow-release process. The lack of homogeneity of this distribution will have a major impact on the rate of release of the appropriate amount of therapeutic drug from the matrix. In this work, we attempt to answer these questions. The performed biological assays revealed that both C12ALA and C12ALA-AuNP show an excellent level of biological neutrality. They might be used as a transporting medium for a drug delivery without affecting the drug's activity.

The increase in conductivity with temperature in 1H-pyrazol-2-ium 2,6-dicarboxybenzoate monohydrate was analyzed, and the influence of the mobility of the water was discussed in this study. The electric properties of the salt were studied using the impedance spectroscopy method. WB97XD/6-311++G(d,p) calculations were performed, and the quantum theory of atoms in molecules (QTAiM) approach and the Hirshfeld surface method were applied to analyze the hydrogen bond interaction. It was found that temperature influences the spectroscopic properties of pyrazolium salt, particularly the carbonyl and hydroxyl frequencies. The influence of water molecules, connected by three-center hydrogen bonds with co-planar tetrameters, on the formation of structural defects is also discussed in this report.