Unraveling the mechanism of ruthenium (III)-catalyzed aspirin oxidation by hexacyanoferrate(III): kinetic and spectrophotometric approach Gupta, Nikita, Rolaniya, Yadav, Jain, Sailani Bulgarian Chemical Communications, 2025 The redox reaction between aspirin and hexacyanoferrate (III), catalyzed by ruthenium (III) in alkaline medium, was thoroughly investigated.The reaction kinetics exhibit a complex dependence on both hydroxide ion and aspirin concentrations, while the reaction order with respect to the oxidant and catalyst is found to be unity.Based on the kinetic results, a plausible reaction mechanism was proposed, and the derived rate law successfully accounts for all experimental observations.Kinetic parameters were evaluated under varying conditions, and activation as well as thermodynamic parameters were accurately determined using the Arrhenius and Eyring equations.
Structure of Mixed Halide Perovskite Nanocrystals at Various Length Scales K. R. Pradeep, Priyanka Jain, K. T. Suhas, Vadim Murzin, Chandrabhas Narayana, Ranjani Viswanatha Journal of Physical Chemistry C, 2024 Understanding the internal structure and bonding of lead halide perovskite nanocrystals (NCs) is crucial to designing stable materials for various applications. In this work, we probe the extent of alloying and phase segregations in mixed halide perovskites at three length scales using a combination of optical spectroscopy, X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), and Raman spectroscopy. We observe domain-free mixed halide solid solutions with randomly distributed halide ions about the Pb center with several distinct but dynamically changing [PbClxBr6–x]4– environments with only Pb–Cl and Pb–Br bonds. They are also sensitive to the changes in the unit cell dimensions resulting from the substitution of Br by Cl, obeying Vegard’s law. Further, we reveal that weak octahedral bonding drives the consistent alteration of the halide environment. These studies provide insights into the chemical bonding driving the improved stability and performance pivotal for designing advanced optoelectronic devices.
Experimental and Computational Kinetic Assessment of Ruthenium (III) Catalyzed Oxidation of Paracetamol by Hexacyanoferrate(III): A Mechanistic Pathway Asha Rolaniya, Akta Yadav, Priyanka Jain, Riya Sailani Chemistryselect, 2024 The ruthenium (III) catalyzed redox reaction of paracetamol with hexacyanoferrate (III) in an acidic medium has been investigated. The reaction shows fractional order dependence respecting paracetamol and first‐order dependence respecting the oxidant and ruthenium (III). It is enhanced by medium according to the equation kobs=a+b[H+]. The activation and thermodynamic parameters of the reaction have been estimated using the Arrhenius and Eyring equations. The oxidation product of paracetamol has been identified as quinone oxime through spectral analysis. Furthermore, the reaction has been examined in nine various organic solvents, and the solvents effect has been investigated by Taft's and Swain's multiparametric equations. The rate constants have been found to correlate well with Kamlet‐Taft's solvatochromic parameters (α, β, π*). The reaction constants have been found to be negative, suggesting that the reactivity is influenced mainly by the solute‐solvent interactions. On the basis of kinetic results, a plausible reaction mechanism has been proposed. The proposed mechanism is reinforced by additional evidence from density functional theory (DFT) computations conducted at b3lyp/6‐311*G (d,p) level, which demonstrate that the activation energy barriers align with the reactivity trend observed in the kinetics experiments. Therefore, these computational results provide further support for the proposed mechanism.
Raman Evidence of Multiple Adsorption Sites and Structural Transformation in ZIF-4 Priyanka Jain, Gayatri Kumari, Meha Bhogra, Premakumar Yanda, Boby Joseph, Umesh V. Waghmare, Chandrabhas Narayana Inorganic Chemistry, 2023 The zeolitic imidazolate framework, ZIF-4, exhibits soft porosity and is known to show pore volume changes with temperatures, pressures, and guest adsorption. However, the mechanism and adsorption behavior of ZIF-4 are not completely understood. In this work, we report an open to narrow pore transition in ZIF-4 around T ∼ 253 K upon lowering the temperature under vacuum (10-6 Torr) conditions, facilitated by C-H···π interactions. In the gaseous environment of N2 and CO2 around the framework, characteristic Raman peaks of adsorbed gases were observed under ambient conditions of 293 K and 1 atm. A guest-induced transition at ∼153 K resulting in the opening of new adsorption sites was inferred from the Raman spectral changes in the C-H stretching modes and low-frequency modes (<200 cm-1). In contrast to a single vibrational mode generally reported for entrapped N2, we show three Raman modes of adsorbed N2 in ZIF-4. The adsorption is facilitated by dispersive and quadrupolar interactions. From our temperature-dependent Raman results and theoretical analysis based on the density functional tight-binding approach, we conclude that the C-Hs are the preferred adsorption sites on ZIF-4 in the following order: C4-H, C5-H > C2-H > center of the Im ring (interacting with C-H centers) > center of the cavity. We also show that with an increasing concentration of N2 adsorbed at low temperatures, the ZIF-4 structure undergoes shear distortion of the window formed by 4-imidazole rings and consequent volumetric expansion. Our results have immediate implications in the field of porous materials and could be vital in identifying subtle structural transformations that may favor or hinder guest adsorption.
Ru(III) Catalyzed Oxidation of Menthol by Bromate in Presence of Mercuric Acetate in Aqueous Acidic Medium: A Kinetic and Mechanistic Pathway Priyanka Jain, Asha Rolaniya, Riya Sailani Russian Journal of Physical Chemistry A, 2022 Kinetic investigation of Ru(III) catalyzed oxidation of menthol in an acidified solution of potassium bromate in the presence of Hg(OAc)2 as a scavenger of bromine intermediate has been studied. The reaction exhibits zero order kinetics with respect to KBrO3. While first order kinetics with respect to menthol and Ru(III) respectively. Hydrogen ion does not affect the rate but rate is enhanced by ionic strength. The influence of Hg(OAc)2 on the rate was found to be insignificant. Menthone as the oxidation product of menthol has been confirmed spectrally. The proposed mechanism involves slow and rate-controlling disproportionate of a transient complex formed between reactive species of Ru(III) and menthol. The various activation parameter such as energy of activation (∆E)#, Arrhenius factor (A), and entropy of activation (∆S)# were calculated. The rate law derived on the basis of experimental data corresponds well with the proposed mechanism.
Polaronic Signatures in Doped and Undoped Cesium Lead Halide Perovskite Nanocrystals through a Photoinduced Raman Mode Priyanka Jain, Madhulika Mazumder, K. R. Pradeep, Ranjani Viswanatha, Swapan K. Pati, Chandrabhas Narayana ACS Applied Materials and Interfaces, 2022 Lead halide perovskites (LHPs) are promising candidates for photovoltaic applications as they exhibit large carrier diffusion lengths and long carrier lifetimes among many other interesting properties. One of the widely accepted mechanisms for these properties is polaron formation, which is mainly driven by octahedral distortions of the inorganic framework. Since structure modifications of the framework largely affect associated distortions, we investigated Mn-doped and undoped CsPbX3 (where X = Cl, Br, Cl/Br) using a local probe via micro-Raman spectroscopy and density functional theory (DFT) calculations for polaron formation. Our results highlight a new vibrational lattice mode at 132 cm–1 due to polaronic distortion upon photoinduction. From the DFT studies, we have shown that the polaronic states are dominated by the B-site cation in the perovskite structure, but it is the strong covalent overlap of the halide which determines its stability. This elucidation to map polaronic signatures with excellent spatial resolution using traditional Raman spectroscopy can be used as a simple tool to understand the structural changes and their impacted electronic properties and thus design superior devices using its in situ applications.
OXIDATION OF NICOTINIC ACID BY PERMANGANATE IN ACID PERCHLORATE MEDIUM – A KINETIC AND MECHANISTIC PATHWAY Oxidation Communications, 2022
Phase Transitions in Materials Divya Chalapathi, Priyanka Jain, Chandrabhas Narayana Advances in the Chemistry and Physics of Materials Overview of Selected Topics, 2019
Kinetics and mechanism of ruthenium(III) chloride catalyzed oxidation of formic acid by peroxomonosulphuric acid in acid aqueous medium - An appraisal of hydride ion transfer Journal of the Indian Chemical Society, 2010
Kinetics and mechanism of oxidation of azide with peroxomonosulphate in acetate buffers Oxidation Communications, 2006
RECENT SCHOLAR PUBLICATIONS
Electron Transfer Oxidation Kinetics of Copper (II) Catalyzed Reaction between Lysine and HCF (III): An Experimental and Theoretical Approach A Yadav, A Rolaniya, P Jain, R Sailani Journal of the Indian Chemical Society, 101931 , 2025 2025 Citations: 1
Osmium (viii)-catalyzed oxidative degradation of paracetamol by chloramine-T in an aqueous alkaline medium: computational screening and mechanistic pathways D Pareek, A Rolaniya, A Yadav, M Bhasin, A Meena, M Ranka, P Jain, ... RSC advances 15 (39), 32609-32617 , 2025 2025
Experimental and computational kinetic evaluations of silver (i)-catalyzed oxidation of p-chlorophenol by hexacyanoferrate (iii): exploring the mechanistic pathway A Rolaniya, A Yadav, P Jain, R Sailani Physical Chemistry Chemical Physics 27 (4), 2023-2032 , 2025 2025 Citations: 3
Experimental and computational kinetic assessment of ruthenium (III) catalyzed oxidation of paracetamol by hexacyanoferrate (III): a mechanistic pathway A Rolaniya, A Yadav, P Jain, R Sailani ChemistrySelect 9 (2), e202303734 , 2024 2024 Citations: 9
Ru (III) Catalyzed Oxidation of Menthol by Bromate in Presence of Mercuric Acetate in Aqueous Acidic Medium: A Kinetic and Mechanistic Pathway P Jain, A Rolaniya, R Sailani Russian Journal of Physical Chemistry A 96 (11), 2381-2386 , 2022 2022 Citations: 1
OXIDATION OF NICOTINIC ACID BY PERMANGANATE IN ACID PERCHLORATE MEDIUM-A KINETIC AND MECHANISTIC PATHWAY. A AGRAWAL, A YADAV, P JAIN, R SAILANI Oxidation Communications 45 (2) , 2022 2022
Kinetics and mechanism of ruthenium (III) chloride catalyzed oxidation of formic acid by peroxomonosulphuric acid in acid aqueous medium-An appraisal of hydride ion transfer P Jain, R Sailani, G Singh, CL Khandelwal, PD Sharma Journal of the Indian Chemical Society 87 (7), 817-822 , 2010 2010 Citations: 1
Kinetics and mechanism of oxidation of azide with peroxomonosulphate in acetate buffers P Jain, S Dubey, CL Khandelwal, PD Sharma OXIDATION COMMUNICATIONS 29 (4), 881-887 , 2006 2006 Citations: 1
MOST CITED SCHOLAR PUBLICATIONS
Experimental and computational kinetic assessment of ruthenium (III) catalyzed oxidation of paracetamol by hexacyanoferrate (III): a mechanistic pathway A Rolaniya, A Yadav, P Jain, R Sailani ChemistrySelect 9 (2), e202303734 , 2024 2024 Citations: 9
Experimental and computational kinetic evaluations of silver (i)-catalyzed oxidation of p-chlorophenol by hexacyanoferrate (iii): exploring the mechanistic pathway A Rolaniya, A Yadav, P Jain, R Sailani Physical Chemistry Chemical Physics 27 (4), 2023-2032 , 2025 2025 Citations: 3
Electron Transfer Oxidation Kinetics of Copper (II) Catalyzed Reaction between Lysine and HCF (III): An Experimental and Theoretical Approach A Yadav, A Rolaniya, P Jain, R Sailani Journal of the Indian Chemical Society, 101931 , 2025 2025 Citations: 1
Ru (III) Catalyzed Oxidation of Menthol by Bromate in Presence of Mercuric Acetate in Aqueous Acidic Medium: A Kinetic and Mechanistic Pathway P Jain, A Rolaniya, R Sailani Russian Journal of Physical Chemistry A 96 (11), 2381-2386 , 2022 2022 Citations: 1
Kinetics and mechanism of ruthenium (III) chloride catalyzed oxidation of formic acid by peroxomonosulphuric acid in acid aqueous medium-An appraisal of hydride ion transfer P Jain, R Sailani, G Singh, CL Khandelwal, PD Sharma Journal of the Indian Chemical Society 87 (7), 817-822 , 2010 2010 Citations: 1
Kinetics and mechanism of oxidation of azide with peroxomonosulphate in acetate buffers P Jain, S Dubey, CL Khandelwal, PD Sharma OXIDATION COMMUNICATIONS 29 (4), 881-887 , 2006 2006 Citations: 1
Osmium (viii)-catalyzed oxidative degradation of paracetamol by chloramine-T in an aqueous alkaline medium: computational screening and mechanistic pathways D Pareek, A Rolaniya, A Yadav, M Bhasin, A Meena, M Ranka, P Jain, ... RSC advances 15 (39), 32609-32617 , 2025 2025
OXIDATION OF NICOTINIC ACID BY PERMANGANATE IN ACID PERCHLORATE MEDIUM-A KINETIC AND MECHANISTIC PATHWAY. A AGRAWAL, A YADAV, P JAIN, R SAILANI Oxidation Communications 45 (2) , 2022 2022
