Thermophysical properties including density (ρ), speed of sound (u), specific conductivity (κ), and refractive index (n D ) for binary mixtures of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide with Triton X-45 and Triton X-100 have been studied over the entire composition range at different temperatures (293.15 to 323.15) K. Further the excess molar volume (V E ), deviations in isentropic compressibility (ΔK S ), deviation in specific conductivity (Δκ), deviation in molar refractive index (ΔR), and partial molar quantities, viz., partial molar excess volume (V i E ), and partial molar deviation in isentropic compressibility (ΔK S,i ), have also been evaluated. In order to gain insight into molecular interactions taking place between different components of the binary mixtures, spectroscopic properties, viz., FT-IR and 1 H and 13 C FT-NMR spectroscopy of these binary mixtures, have been measured and analyzed. The measured thermophysical parameters and their excess values have been used to interpret the structural and interactional behavior of studied formulations. It has been seen that V E , ΔK S , Δκ, and ΔR results are in agreement, which confirms that the addition ofa number of oxyethylene groups in Tritons and a rise in temperature resulted in stronger intermolecular interactions. FT-NMR and FT-IR results reveal that interactions are mainly taking place via π−π stacking between two rings of both components.

The direct and selective introduction of hydroxyl group into aromatic compounds remains one of the challenging problems in oxidation chemistry. Keeping in view the reported reactivity of vanadium oxide in C-H activation of saturated hydrocarbons, the study explores the reactivity of neutral VO cluster with benzene through rigorous computations performed within the formalism of density functional theory. Three possible reaction channels for the reactivity of VO cluster with benzene have been deciphered, and comprehensive understanding of all possible mechanistic pathways has been obtained by analysis of all the intermediates and transition states encountered en route. The study provides promising evidence of direct abstraction of hydrogen by terminal oxygen of the cluster via three-centered transition state. The scan of potential energy surfaces for the reactivity of the cluster in its ground (singlet) and first excited (triplet) spin multiplicity states establishes two-state reactivity mechanisms. The spin crossover point has been identified through geometric and thermodynamic parameters, partial charges, and intrinsic reaction coordinate calculations. The study establishes the efficacy of VO cluster species in direct hydroxylation of benzene to phenol.

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In the present study, we explored the sensing behavior of pristine gCN and transition metal (Au, Ag, Pd and Pt) doped gCN monolayer for CO gas molecule using DFT calculations. Structural and electronic properties such as adsorption energy, band structure and density of states (DOS) have been investigated. An increase of 17.03%, 15.08%, 2.24% and 4.99% is observed for Au, Ag, Pd and Pt doped gCN as compared to pristine gCN towards CO gases. Moreover the band gap also decreases considerably after doping transition metals in it which futher reduces after introduction of CO gas. DOS value also increases. The study revealed that the sensing performance of gCN is enhanced by doping the pristine form with the transition metals (Au, Ag and Pt) and hence doped gCN can be a favorable material for CO gas sensing.

The structural and energetic properties of small silver clusters Agn with n = 2–100 atoms are reported. For n = 2–100 the embedded atom model for the calculation of the total energy of a given structure in combination with the basin-hopping search strategy for an unbiased structure optimization has been used to identify the energies and structures of the three energetically lowest-lying isomers. These optimized structures for n = 2–11 were subsequently studied further through density-functional-theory calculations. These calculations provide additional information on the electronic properties of the clusters that is lacking in the embedded-atom calculations. Thereby, also quantities related to the catalytic performance of the clusters are studied. The calculated properties in comparison to other available theoretical and experimental data show a good agreement. Previously unidentified magic (i.e., particularly stable) clusters have been found for n>80. In order to obtain a more detailed understanding of the structural properties of the clusters, various descriptors are used. Thereby, the silver clusters are compared to other noble metals and show some similarities to both copper and nickel systems, and also growth patterns have been identified. All vibrational frequencies of all the clusters have been calculated for the first time, and here we focus on the highest and lowest frequencies. Structural effects on the calculated frequencies were considered.