Applications of Density Functional Theory on Heavy Metal Sensor and Hydrogen Evolution Reaction (HER)

A great effort has been devoted to develop the numerical methods to solve Schrödinger equation for atoms and molecules which help to reveal the physico-chemical process and properties of various known/unknown materials. Designing the efficient probe to sense the heavy metals is a crucial process in chemistry. And, during this energy crisis, to find the effective conversion materials for water splitting is an important approach. The density functional theory (DFT) is a powerful tool to identify such materials and made great achievements in the field of heavy metal chemosensor and photocatalysis. Particularly, DFT helps to design the chemosensor for the effective sensor applications. The universe is moving towards the exhaustion of fossil fuels in a decade and so on, DFT plays a vital role to find the green energetic alternative to fossil fuel which is the Hydrogen energy. This book chapter will focus on the application of DFT deliberately on the heavy metal sensors and hydrogen evolution reaction

Computations on Three Isomers of La@C 74

ABSTRACT: Density-functional theory calculations are presented for La@C 74 , where C 74 is either the IPR (isolated pentagon rule) cage or two cages with a pentagon-pentagon junction. Their relative thermodynamic production yields are evaluated using the calculated terms, and it is shown that the IPR-based endohedral prevails at relevant temperatures in agreement with the observation

Lix@C60: Calculations of the Encapsulation Energetics and Thermodynamics

Li@C60 and Li@C70 can be prepared and thus, their calculations at higher levels of theory are also of interest. In the report, the computations are carried out on Li@C60, Li2@C60 and Li3@C60 with the B3LYP density-functional theory treatment in the standard 3-21G and 6-31G* basis sets. The computed energetics suggests that Lix @C60 species may be produced for a few small x values if the Li pressure is enhanced sufficiently. In order to check the suggestion, a deeper computational evaluation of the encapsulation thermodynamics is carried out

Theoretical Study of 3d-Metal Mononitrides Using DFT Method

ABSTRACT: 3d-Metal mononitrides are studied using the density functional theory method. The lowest spin state for these dimers is obtained using the B3LYP hybrid functional with the 6-311ϩG* basis set. The equilibrium geometries, vibrational frequencies, binding energies, Mulliken, and natural orbital population analysis charges, natural orbital electronic configuration, electron affinity, and ionization potential are obtained. Mulliken as well as natural orbital population analysis charges indicate that for all dimers, in cations most of the positive charge localized on the transition metal atom where in anions most of the negative charge localized on nitrogen atom. The binding energies for 3d-metal mononitrides are higher than those for monocarbides and monoxides

Many-body interactions of carbon monoxide cyclic oligomers: A computational study

ABSTRACT: Structural properties and energetics for the optimized carbon monoxide cyclic oligomers are analyzed at the correlated ab initio second-order Møller-Plesset (MP2) and density functional methods (B3LYP and mPW1PW), using Dunning's ccpVXZ (X ϭ D, T, Q) basis set, augmented with diffuse functions. Many-body interactions of the stable carbon monoxide cyclic oligomers, (CO) 4 and (CO) 5 are computed at the MP2/aug-cc-pVTZ level. Contributions of two-to five-body terms to each of these oligomers for their interaction energies, including corrections for basis set superposition error (BSSE) are investigated by using function counterpoise and its generalized version. It has been found that three-body terms are attractive in nature and essential in order to describe the cooperative effects in the stable cyclic CO oligomers

Some recent results in the theory of the Wiener number

651-661The Wiener number (W) is equal to the some of distances between all pairs of vertices of the molecular graph. This important topological index was invented in the 1940, but vigorous research on both its theory and its applications is still going on. The aim of this article is to outline the state of the art of the theory of the Wiener number, with emphasis on the progress achieved in the last few years. In particular, we present (a) the recent results on the relation between W and intermolecular forces (which, for the first time, provide a sound physico-chemical basis for various applications of W), (b) several novel techniques for the calculation of W, (c) methods for the calculation of W of composite and highly branched molecular graphs, (d) the problem of isomer degeneracy of W, and (e) some novel mathematical results relevant to the theory of W

Dynamic scaling of diffusion-limited reactions over fractal surfaces: computer simulation

Abstract Computer simulations are performed to examine the effect of geometrical heterogeneity on chemical reaction occurring over a fractal surface of diffusion-limited aggregation (DLA). Eley-Rideal diffusion-limited reaction (DLA) is chosen as our model reaction system. Dynamic scaling theory, developed for surface growth model, is applied in this work on chemical reaction model revealing two order parameters, a and b, in different time domains, i.e. a ¼ À0:74, b ¼ À0:48 for perfect sticking cases, and a ¼ À0:72, b ¼ À0:5 for cases of lower sticking probability. Surfaces of different fractal dimensions are also considered, where the values of b in both cases and a values in the perfect sticking case do not change obviously. In the cases of lower sticking probability, a values are decreased when fractal dimension approaches to 2. Comparisons are made to the surface roughening model where both order parameters are positive.

Chemical applications of the Laplacian spectrum of molecular graphs: Studies of the Wiener number

603-608The Wiener number (W) of an acyclic molecule can be expressed as a function of the Laplacian spectrum of the corresponding molecular graph. This algebraic relation enables inferences about the dependence of W on molecular structure. The graph invariants which determine the gross part-some 98% or more of W-are identified. As a consequence of this an approximate formula for W is obtained which is capable of reproducing W of the molecular graphs of alkanes with an error of about 2%

The Lattice Kinetic Monte Carlo Simulation of Boron Diffusion in SiGe

De bekende Duitse website Archivalia heeft de archiefzoeker ontdekt. http://archiv.twoday.net/stories/6106307 Als u archiefonderzoek in Duitsland moet verrichten is deze website een “must”. http://archieven.blogspot.com/2009/12/nieuwsbrief-archiefforum.htm