Bhaskar Mondal

Indian Institute of Technology Mandi | भारतीय प्रौद्योगिकी संस्थान मंडी · School of Basic Sciences

As the postsynthesis-processed metal-organic material-based catalysts for energy applications add additional cost to the whole process, the importance of developing synthesized usable pristine catalysts is quite evident. The present work reports a new Cu-based coordination polymer (Cu-CP) catalyst to be used in its pristine form for oxygen reductio...

The importance of the orientation of functional groups in a chiral environment on enantioselective recognition has been demonstrated. Orientation controlled interactions of functional groups in (R)/(S)-MA lead to visually differentiable...

The structure-functional relationship, especially the origin of absorption and emission of light in carbon nanodots (CNDs) has baffled the scientists. The multilevel complexity arises due to the large number of un-attentive by-products synthesized in the bottom-up approach. By performing a systematic purification and characterization, we unveil the...

Conversion of CO2 into liquid fuels and value-added fine chemicals has gained much attention in recent years to meet the ever-rising global energy demand and hence develop a sustainable solar fuel economy. This chapter enumerates feasible catalytic routes through which CO2 could be utilized as a C1 feedstock. First, we address CO2 functionalization...

The conversion of CO2 into liquid fuels and value-added fine chemicals is of significant interest for both environment and global energy demand. In this frontier article, we highlight viable methods for transforming CO2 into valuable C1 feedstocks and summarize the key mechanistic aspects obtained by in-depth computational investigations of three i...

Oxidative coupling is a useful tool to synthesize vinylarenes. Despite remarkable successes in linear vinylarene, branched vinylarene synthesis has remained underdeveloped. Overcoming this limitation, herein we report a chelation assisted oxidative coupling to generate branched olefinated product in high yield. Exclusive branched selectivity was ob...

Iron(V)-nitrido and -oxo complexes have been proposed as key intermediates in a diverse array of chemical transformations. Herein we present a detailed electronic-structure analysis of [FeV(N)(TPP)] (1, TPP2– = tetraphenylporphyrinato), and [FeV(N)(cyclam-ac)]+ (2, cyclam-ac = 1,4,8,11-tetraazacyclotetradecane-1-acetato) using electron paramagnetic...

Computational chemistry is an increasingly versatile tool for understanding chemical reactions at an atomic level and designing new species with tailored properties. Calculations are often considered as the first line of attack in rational catalyst development because experimental work through trial‐and‐error methods is often not very efficient and...

Fixation and chemical reduction of CO 2 are important for utilization of this abundant resource, and understanding the detailed mechanism of CO cleavage is needed for rational development of CO 2 reduction methods. Here, we describe a detailed analysis of the mechanism of the reaction of a masked two-coordinate cobalt(I) complex, L tBu Co (where L...

Oxo-iron(V) species have been implicated in the catalytic cycle of the Rieske dioxygenase. Its synthetic analog, [FeV(O)(OC(O)CH3)(PyNMe3)]2+ (1, PyNMe3 = 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene-3,6,9- trimethyl), derived from the O–O bond cleavage of its acetylperoxo iron(III) precursor, has been shown experimentally to perform...

C–H bond activation mediated by oxo-iron(IV) species represents the key step of many heme and non-heme O2-activating enzymes. Of crucial interest is the effect of spin state of the FeIV(O) unit. Here we report the C–H activation kinetics and corresponding theoretical investigations of an exclusive tetracarbene ligated oxo-iron(IV) complex, [NHCLFeI...

In biology, high valent oxo-iron(IV) species have been shown to be pivotal intermediates for functionalization of C-H bonds in the catalytic cycles of a range of O2-activating iron enzymes. This work details an electronic-structure investigation of [FeIV(O)(LNHC)(NCMe)]2+ (LNHC = 3,9,14,20-tetraaza-1,6,12,17-tetraazoniapenta-cyclohexacosane-1(23),4...

Multiple-bonded iron-oxo and -nitrido species have been identified or proposed as key intermediates in a range of important chemical transformations. The reported model complexes feature various coordination geometries and distinct electronic structures, and therefore exhibit diverse reactivity. The present contribution highlights the synergy from...

Carbon dioxide functionalization attracts much interest due to the current environmental and energy challenges. Our earlier work (Mondal, B.; Neese, F.; Ye, S. Inorg. Chem. 2015, 54, 7192-7198) demonstrated that CO2 hydrogenation mediated by base metal catalysts [M(H)(η(2)-H2)(PP3(Ph))](n+) (M = Co(III) and Fe(II), n = 1, 2; PP3(Ph) = tris(2-(diphe...

The development of efficient catalysts with base metals for CO2 hydrogenation has always been a major thrust of interest. A series of experimental and theoretical work has revealed that the catalytic cycle typically involves two key steps, namely, base-promoted heterolytic H2 splitting and hydride transfer to CO2, either of which can be the rate-de...

The global energy and environmental concerns related to the excess CO2 concentration in the atmosphere have intensified the research and development regarding CO2 utilization. Due to the high stability and inertness of CO2, CO2 functionalization under mild conditions has been proven to be extremely challenging. Nature has, however, evolved efficien...

A series of robust iridium(I) complexes bearing a sterically encumbered N‐heterocyclic carbene ligand, alongside a phosphine ligand, has been synthesised and investigated in hydrogen isotope exchange processes. These complexes have allowed isotope incorporation over a range of substrates with the use of practically convenient deuterium and tritium...

The use of alternative solvents in the iridium-catalysed hydrogen isotope exchange reaction with developing phosphine/NHC Ir(i) complexes has identified reaction media which are more widely applicable and industrially acceptable than the commonly employed chlorinated solvent, dichloromethane. Deuterium incorporation into a variety of substrates has...

Recent papers report transition metal-free couplings of haloarenes to arenes to form biaryls, triggered by alkali metal tert-butoxides in the presence of various additives. These reactions proceed through radical intermediates, but understanding the origin of the radicals has been problematic. Electron transfer from a complex formed from potassium...

The inside cover picture, by Kerr and co-workers depicts a series of robust, yet highly active Ir(I) complexes bearing specifically encumbered N-heterocyclic carbene and phosphine ligands. These complexes are extremely effective in hydrogen isotope exchange processes (with D or T), with low catalyst loadings, good levels of selectivity, and broad d...

Dispersion corrected density functional theory (DFT-D) has been applied to understand the performance of several palladium metal scavengers. Nine different sulfur-based ligands and three different palladium metal sets have been investigated in detail. Based on a thorough analysis of the thermodynamic binding parameters ΔH, ΔG and ΔS, we have identi...

The binding properties of a series of benzenesulfonamide inhibitors (4-substituted-ureido-benzenesulfonamides, UBSAs) of human carbonic anhydrase II (hCA II) enzyme with active site residues have been studied using a hybrid quantum mechanical/molecular mechanical (QM/MM) model. To account for the important docking interactions between the UBSAs lig...

The association reaction between silyl radical (SiH3) and H2O2 has been studied in detail using high-level composite ab initio CBS-QB3 and G4MP2 methods. The global hybrid meta-GGA M06 and M06-2X density functionals in conjunction with 6-311++G(d,p) basis set have also been applied. To understand the kinetics, variational transition-state theory ca...

The prevalence of metal-based reducing reagents, including metals, metal complexes and metal salts, has produced an empirical order of reactivity that governs our approach to chemical synthesis. However, this reactivity may be influenced by stabilization of transition states, intermediates and products through substrate-metal bonding. This article...

Spectroscopy, interaction energy, and dissociation of linear and T-shaped isomers of HeClF, NeClF, and ArClF van der Waals complexes in their ground state have been studied in detail using MP2 and CCSD(T) methods in conjunction with correlation consistent valence triple and quadruple zeta basis sets. A method, called potential method, has been deve...

Ab initio and density functional theory (DFT) calculations have been performed to understand the destruction chemistry of an important organophosphorus insecticide O,O-dimethyl O-(3-methyl-4-nitrophenyl) phosphorothioate, fenitrothion (FN), toward nucleophilic attack. Breaking of the P-OAr linkages through nucleophilic attack is considered to be th...

The structure, stability and energetics of ionic arsenic–water complexes [As–nH2O (n = 1–5) and As–nH2O (n = 3–5)] have been studied in detail using the MP2 method. Both the trivalent and pentavalent ionic states of arsenic were considered. The change in binding energy of the complexes with increasing number of water molecules was investigated. For...

The intermediates [Si,O,C,O] of the Si + CO2 reaction have been studied in detail using high level ab iniitio methods. Both singlet and triplet [Si,O,C,O] species are characterized structurally and energetically. On the singlet potential energy surface (PES), the vdw-OSi–CO isomer and in the triplet PES, the bent-SiOCO isomer is found to be thermod...

The potential energy surfaces (PES) for the reaction of the C(2)H radical with 1-butyne (C(4)H(6)) have been studied using the CBS-QB3 method. Density functional B3LYP/cc-pVTZ and M06-2X/6-311++G(d,p) calculations have also been performed to analyze the reaction energetics. For detailed theoretical calculation on the total reaction mechanism, the i...

A systematic theoretical study has been performed on the low pressure thermal decomposition pathways of t-BuS(O)St-Bu using the CCSD(T)/cc-pV(D+d)Z//B3LYP/6-311++G(2d,2p), CCSD(T)/cc-pV(D+d)Z//PBEPBE/6-311++G(2d,2p), and G3B3 level of theories. Rate constants for the unimolecular decomposition pathways are calculated using Rice−Ramsperger−Kassel−Ma...

The isomers of the carbonyl sulfide (OCS) molecule are investigated in detail at CCSD(T)/cc-pVTZ//MP2/6-311++G(2d,2p) level of theory. One cyclic isomer was identified along with three different linear minima of the OCS molecule. Three interconversion transition states were also located between cyclic and linear forms of OCS. Among these four isome...

The gas-phase isomerization and decomposition reactions of dimethyl ethylphosphonate (DMEP) are investigated using the CBS-QB3 method followed by the calculation of rate constant for all reaction pathways using Rice-Ramsperger-Kassel-Marcus (RRKM) theory. Three conformational isomers C1, C2, and C3 are identified for DMEP having stability order C1...

Structure, stability, and dissociation of H2BSiN, H2NSiN, H2PSiN and their isomers H2BNSi, H2NNSi, H2PNSi have been studied in detail using ab initio MP2 and CCSD(T) methods. After dissociation of H2BNSi, H2NNSi, H2PNSi and their isomers, the fragmented atoms have been considered to be either in their ground state or in their valence excited state...

The structures, stability, thermochemistry and dissociation of the doublet [H,S,Si,O] species are studied using UMP2-FC and UCCSD(T)-FC methods. Twelve isomers connected with sixteen interconversion transition states are located on the doublet potential energy surface (PES). All isomers are planar except two cyclic isomers. The trans-HOSiS isomer i...

The reaction pathways for the gallium nitride GaN growth by gas phase reaction of trimethylgallium (TMG) with ammonia is studied theoretically. Water is the most important impurity in ammonia, therefore its reaction with TMG is investigated as a possible source of oxygen impurity in GaN. Gallium oxide (GaO) formed by the reaction between TMG and H(...

The structures, vibrational frequencies, enthalpies of formation and dissociation energies of arsine, arsenic hydrides and their fluoro, chloro derivatives have been studied using density functional B3LYP/cc-pVDZ, ab-initio MP2/cc-pVDZ and composite CBS-QB3 and CBS-Q methods. Computed standard enthalpies of formation at 298 K by atomisation scheme...

Gas phase reaction between germane GeH4 and water H2O was investigated at CCSD(T)/[aug-cc-pVTZ-pp for Ge+Lanl2dz for H and O]//MP2/6-31G(d,p) level. Only the hydrogen elimination channels are monitored. Within the energy range of 100kcal/mol, we located nine equilibrium and six transition states on the potential energy surface (PES) of the Ge–O–H s...

An ab initio study has been performed to characterize the probable magnesium containing interstellar species MgSiN, MgNSi and their ionized, hydrogenated and protonated forms. We are able to locate four protonated and four hydrogenated magnesium species with planar geometry at MP2(Full)/cc-pVTZ level of theory. MgNSi is found to be more stable than...

The spectroscopy and dissociation of the sulfuryl halides SO2F2 and SO2Cl2 have been studied in detail using ab initio methods. The possibility of various dissociation channels has been explored taking into account that the fragmented atoms and molecules can stay in their ground state only. An interesting pattern was observed in their dissociation...

Reaction between SiO2 and water has been studied extensively using ab initio methods. The mechanism for formation of metasilicic acid SiO(OH)2 and orthosilicic acid Si(OH)4 has been explored and a new pathway for formation of Si(OH)4 is predicted. Heats of reaction (ΔrH298∘) and heats of formation (ΔfH298∘) at 298K for the related reactions and spe...

Spectroscopy and dissociation of the sulfuryl halides SO2Br2 and SO2I2 have been studied in detail using ab initio MP2 and CCSD(T) methods. The discrepancy among the recent theoretical works for the assignment of harmonic vibrational frequencies of SO2Br2 has been addressed. The possibility of various dissociation channels has been explored conside...

Dissociation and thermochemistry of CH3SiN and SiH3SiN have been studied in detail using high level quantum chemical methods. The enthalpy of formation of these molecules at 0 K and 298.15 K are predicted by G3 and G3//B3LYP methods using an atomization scheme. The bond dissociation energy and energy barrier for the dissociation pathways are estima...

Stability, spectroscopic constants, and dissociation of CO2+ have been studied in detail using ab initio MP2, CCSD and CCSD(T) methods, and density functional B3LYP method. The stability and the ambiguity between the ground and metastable state of the molecular dication have been discussed. The spectroscopic constants of the molecular dication have...

Structural properties and dissociation of cyanogen bromide BrCN, cyanogen iodide ICN, and their isomers have been studied in detail using ab initio MP2, CCSD, and CCSD(T) methods. After dissociation of BrCN and ICN, the fragmented atoms have been considered to be either in their ground state or in their valence excited states. The recent experiment...