A systematic study on the structure and stability of nitrate anion hydrated clusters, NO3(-) x n H2O (n = 1-8) are carried out by applying first principle electronic methods. Several possible initial structures considered for each size cluster to locate equilibrium geometry a correlated hybrid density functional with 6-311++G(d,p) basis function. Three different types arrangements, namely, symmetrical double hydrogen bonding, single bonding inter-water obtained in these clusters. having is...

The recent outbreak of the coronavirus (COVID-19) pandemic, caused by SARS-CoV-2 virus, has posed serious threats to global health systems. Although several directions have been put WHO for effective treatment, use antibiotics, particularly ciprofloxacin, in suspected and acquired Covid-19 patients raised an even more concern antibiotic resistance. Ciprofloxacin reported inhibit entry into host cells via interacting with spike (S) protein. However, a proper structure-activity relationship...

The water-soluble trinuclear Pd metallacycles [Pd(tmeda)(4-Spy)]3(X)3 (tmeda = tetramethylethylenediamine, X OTf, 2; NO3, 3) were synthesized from the ambidentate ligand 4-pyridylthiolate (Spy–) and [Pd(tmeda)X2] in 80 70% yield, respectively. Two possible linkage isomers are found solution (slow interconversion NMR) solid state. Density functional calculations showed that energy of isomer with a D3-symmetric arrangement SPy all atoms having N∧NPdSN coordination is only 7 kcal/mol lower....

The structural, mechanical and elastic properties of industrially important C‐type lanthanide sesquioxides, Ln 2 O 3 (Ln = Pm, Sm, Eu, Gd, Tb, Dy), are studied by employing ab initio electronic structure calculations. calculated lattice parameters for match very well with the experimental crystal structures clearly reproduce contraction across series. Similarly, constants, bulk modulus other obtained from our calculations in good agreement values available literature. knowledge about shear...

The work presents ab initio results on structure and electronic properties of Br2*-.nH2O(n=1-10) Br2.nH2O(n=1-8) hydrated clusters to study the effects an excess electron microhydration halide dimer. A nonlocal density functional, namely, Becke's half-and-half hybrid exchange-correlation functional is found perform well present systems with a split valence 6-31++G(d,p) basis function. Geometry optimizations for all are carried out several initial guess structures without imposing any...

Structure and properties of hydrated clusters halogen gas, X2·nH2O (X = Cl, Br, I; n 1−8) are presented following first principle based electronic structure theory, namely, BHHLYP density functional second-order Moller−Plesset perturbation (MP2) methods. Several geometrical arrangements considered as initial guess structures to look for the minimum energy equilibrium by applying 6-311++G(d,p) set basis function. Results on X2−water Br I) suggest that X2 exists a charge separated ion pair,...

Despite the fact that polarizability of water is different in bulk and protein, simulations protein-ligand complexes are mostly carried out nonpolarizable media. We present oxime (HI-6) unbinding from active site gorge AChE, known to be strongly influenced by intermolecular cation-π, hydrogen bridge (HB) (WB) interactions molecular with effective polarization polarizable mean-field model TIP3P water. Enabled recent availability a method obtaining microkinetics rare events, we set investigate...

The self-assembly of Xantphos-capped M(OTf)2 (M = cis-[M′(Xantphos)]2+; M′ Pd, Pt) with bridging ligands 1,4-benezenedithiol or 4,4′-biphenyldithiol has been investigated. reactions have yielded complexes [M{S(C6H4)nSH}]2(OTf)2 (I) and [M2{S(C6H4)nS}]2(OTf)4 (II) (n 1 2). equilibrium between I II established in platinum for n 2, whereas the analogous Pd complex exclusively exist as II. These results are different from our previously reported dppe triethyl phosphine-capped which showed only...

Weighted average IR spectra of CO(3)(*-).nH(2)O (n = 1-6) clusters are reported and compared with those CO(3)(2-).nH(2)O based on quantum chemical calculations. Simulated annealing combined the Monte Carlo sampling method is also applied to locate global minimum energy structure. It observed that hydrated CO(3)(*-) ion having cyclic water networks most stable structure in each size cluster. bands at lower side O-H stretching region correspond single/double hydrogen bonding interaction,...

Oral polio vaccine is considered to be the most thermolabile of all common childhood vaccines. Despite heavy water (D2O) having been known for a long time stabilise attenuated viral RNA against thermodegradation, molecular underpinnings its mechanism action are still lacking. Whereas, understanding basis D2O an important step that might reform way other drugs stored and could possibly minimize cold chain problem. Here using combination parallel tempering well-tempered metadynamics simulation...

A new general relation is derived for the size-dependent detachment energy of solvated negatively charged ions in finite size clusters based on a microscopic theory systems with unknown interaction potentials. The tested over large number different kinds finite-size hydrated type Aq−(H2O)n (for spherical and nonspherical, singly multiply ion Aq−), an excellent agreement experimental results observed. More importantly, robust scheme shown to provide route obtain bulk (infinite-size clusters)...

Because of the pivotal role that nerve enzyme, acetylcholinesterase plays in terminating impulses at cholinergic synapses. Its active site, located deep inside a 20 Å gorge, is vulnerable target lethal organophosphorus compounds. Potent reactivators intoxicated enzyme are nucleophiles, such as bispyridinium oxime binds to peripheral anionic site and through suitable cation–π interactions. Atomic scale molecular dynamics free energy calculations explicit water used study unbinding pathways...

We report vertical detachment energy (VDE) and IR spectra of Br2.-.(H2O)n clusters (n=1-8) based on first principles electronic structure calculations. Cluster structures are calculated at Becke's half-and-half hybrid exchange-correlation functional (BHHLYP) with a triple split valence basis function, 6-311++G(d,p). VDE for the hydrated is second order Moller-Plesset perturbation (MP2) theory same set function. On full geometry optimization, it observed that conformers having interwater...

The authors report theoretical results on structure, bonding, energy, and infrared spectra of iodine dimer radical anion hydrated clusters, I(2) (-).nH(2)O (n=1-8), based a systematic study following density functional theory. Several initial guess structures are considered for each size cluster to locate minimum energy conformers with Gaussian 6-311++G(d,p) split valence basis function (triple 6-311 set is applied iodine). It observed that three different types hydrogen bonded structures,...

The vibrational (IR and Raman) photoelectron spectral properties of hydrated iodine-dimer radical-anion clusters, I(2)(*-) x n H(2)O (n=1-10), are presented. Several initial guess structures considered for each size cluster to locate the global minimum-energy structure by applying a Monte Carlo simulated annealing procedure including spin-orbit interaction. In Raman spectrum, hydration reduces intensity I-I stretching band but enhances O-H water. spectra more highly clusters appear be...

Despite the fact that fluorination makes a drug more lipophilic, molecular level understanding of protein-fluorinated interactions is very poor. Due to their enhanced ability penetrate blood brain barrier, they are suitable for reactivation organophosphorus inactivated acetylcholinesterase (AChE) in central nervous system. We systematically studied unbinding fluorinated obidoxime (FOBI) and non-fluorinated (OBI) from active site gorge serine hydrolase AChE mean field polarizable water by...

Pd macrocycles of diphosphine were constructed employing 4-pyridylselenolate. They act as excellent catalysts in the Suzuki coupling reaction.

We present the results of a detailed study on structure and electronic properties hydrated cluster Cl2∙−∙nH2O (n=1–7) based nonlocal density functional, namely, Becke’s [J. Chem. Phys. 98, 1372 (1993)] half hybrid exchange-correlation functional with split valence 6-311++G(d,p) basis function. Geometry optimizations for all clusters are carried out various possible initial guess structures without any symmetry restriction. Several minimum energy (conformers) predicted small difference in...

Temperature induced dynamical transition (DT), associated with a sharp rise in molecular flexibility, is well-known to be exhibited between 270 and 280 K glycerol 200–230 hydrated biomolecules controlled by diffusivity (viscosity) of the solvation layer. In dynamics (MD) community, especially for water as solvent, this has been an intense area research despite decades investigations. However, general, these studies described empirical nonpolarizable force fields which electronic...