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Organic solar cells (OSCs) made of electron-acceptor and electron-donor materials have significantly developed in the last decade, demonstrating their enormous potential in cutting-edge optoelectronic applications. Consequently, we designed seven novel non-fused ring electron acceptors (NFREAs) (BTIC-U1 to BTIC-U7) using synthesized electron-deficient diketone units and reported end-capped acceptors, a viable route for augmented optoelectronic properties. The DFT and TDDFT approaches were used to measure the power conversion efficiency (PCE), open circuit voltage (Voc), reorganization energies (λh, λe), fill factor (FF), light harvesting efficiency (LHE) and to evaluate the potential usage of proposed compounds in solar cell applications. The findings confirmed that the photovoltaic, photophysical, and electronic properties of the designed molecules BTIC-U1 to BTIC-U7 are superior to those of reference BTIC-R. The TDM analysis demonstrates a smooth flow of charge from the core to the acceptor groups. Charge transfer analysis of the BTIC-U1:PTB7-Th blend revealed orbital superposition and successful charge transfer from HOMO (PTB7-Th) to LUMO (BTIC-U1). The BTIC-U5 and BTIC-U7 outperformed the reference BTIC-R and other developed molecules in terms of PCE (23.29% and 21.18%), FF (0.901 and 0.894), normalized Voc (48.674 and 44.597), and Voc (1.261 eV and 1.155 eV). The proposed compounds enclose high electron and hole transfer mobilities, making them the ideal candidate for use with PTB7-Th film. As a result, future SM-OSC design should prioritize using these constructed molecules, which exhibit excellent optoelectronic properties, as superior scaffolds.

Viscosity is the most important characteristic of hydraulic fluid and which is influenced by pressure and temperature. Using statistical methods for correlation analysis and regression, eventual causal relationship between parameters of the Arrhenius-type equation and principally the boiling point of some classical Newtonian liquids is attempted. Empirical validation utilizing data on viscosity of pure Newtonian liquids studied at atmospheric pressure and at different ranges of temperature gives excellent statistical results. Indeed, we found a significant strong correlation between the Arrhenius activation energy (Ea), the Arrhenius temperature (TA), and the boiling point (Tb). Consequently, an original hyperbole-type equation modeling this relationship is proposed which allows the prediction of the boiling temperature and the type of isobaric liquid-vapor diagram through information on viscosity Arrhenius parameters values, only in liquid phase, and will be thus very useful in the handling of engineering data especially for the study of hydraulic components and systems efficiency.

The capability of ccCA, G3, and G3B3 for the prediction of the enthalpies of formation of oxygen fluoride species was evaluated. In addition to these composite methods, the performance of M06 and M06-2X in conjunction with the correlation consistent basis sets (aug-cc-pVnZ), where n = D, T, Q, was also examined for predicting the structures and enthalpies of formation of oxygen fluoride species. A set of various oxygen fluorides were considered, including FOx radicals, FOxH, and FOxF, where x = 1–3. The effects of basis set size and spin contamination were also considered.

The structural stability and internal rotations in cyclopropanecarboxylic acid and cyclopropanecarboxamide were investigated by the DFT-B3LYP and the ab initio MP2 calculations using 6-311G** and 6-311+G** basis sets. The computations were extended to the MP4//MP2/6-311G** and CCSD(T)//MP2/6-311G** single-point calculations. From the calculations the molecules were predicted to exist predominantly in the cis (C O group eclipses the cyclopropane ring) with a cis – trans barrier of about 4–6 kcal/mol. The OCOH torsional barrier in the acid was estimated to be about 12–13 kcal/mol while the corresponding OCNH torsional barrier in the amide was calculated to be about 20 kcal/mol. The equilibrium constant k for the cis ⇔ trans interconversion in cyclopropanecarboxylic acid was calculated to be 0.1729 at 298.15 K that corresponds to an equilibrium mixture of about 85% cis and 15% trans . The vibrational frequencies were computed at the DFT-B3LYP level. Normal coordinate calculations were carried out and potential energy distributions were calculated for the low energy cis conformer of the molecules. Complete vibrational assignments were made on the basis of normal coordinate calculations and comparison with experimental data of the molecules.

The internal rotations in acrylic and methacrylic acids CH2=CX-COOH and their amides CH2=CX-CONH2 (X is H or CH3) were investigated by DFT-B3LYP calculations with 6-311+G** basis set. The potential energy curves were consistent with two minima that correspond to planar cis and trans conformation in the case of the acids (or cis and near-trans forms in the case of the amides). Acrylic acid and acrylamide were predicted to have the cis form as the low and predominant conformation of the molecules. In the case of the methacrylic acid and methacrylamide, the conformational relative stability was predicted to reverse as going from the acrylic to the metha compounds. The trans conformer in methacrylic acid or the near-trans in methacrylamide were predicted to be thermodynamically low energy structures of the molecules. The CCCO rotational barrier was calculated to vary from 4 to 6kcal/mol in the four molecules. The OCOH and OCNH torsional barriers were calculated to be about 13 and 22kcal/mol in the acids and the amides, respectively. The vibrational frequencies of methacrylic acid and methacrylamide were computed at the DFT-B3LYP/6-311+G** level and reliable vibrational assignments were made on the basis of normal coordinate analyses and comparison with experimental data of both molecules in their low energy conformations.