The catalytic asymmetric thiazolium- and triazolium-catalyzed benzoin condensations of aldehydes and ketones were studied with computational methods. Transition-state geometries were optimized by using Morokuma's IMOMO [integrated MO (molecular orbital) + MO method] variation of ONIOM (n-layered integrated molecular orbital method) with a combination of B3LYP/6-31G(d) and AM1 levels of theory, ...

To provide a new idea for drug design, a computational investigation is performed on chymase and its novel 1,4-diazepane-2,5-diones inhibitors that explores the crucial molecular features contributing to binding specificity. Molecular docking studies of inhibitors within the active site of chymase were carried out to rationalize the inhibitory properties of these compounds and understand their ...

The protonation of different species of glycylisoleucine were studied in the pH range of 1.5 - 10 at25 °C using potentiometric technique. Investigations were performed in sodium perchlorate andtetraethylammonium iodide as background electrolytes at I (0.1, 0.2, 0.3, 0.4, 0.5, and 0.6) moldm-3. The parameters based on the protonation constants were calculated, and their dependenceson ionic stren...

A mechanism for the homogeneous gas-phase decomposition of SiHCl3, SiH2Cl2, and SiH3Cl in hydrogen is derived from the results of ab initio molecular-orbital studies. It consists of 39 reversible elementary reactions among 25 species, including pressure-dependent unimolecular decomposition of the chlorinated silanes and secondary chemistry due to reactions of SiH2, SiHCl, and SiCl2 with one ano...

An orbital energy-based reaction analysis theory is presented as an extension of the orbital-based conceptual density functional theory. In the orbital energy-based theory, the orbitals contributing to reactions are interpreted to be valence orbitals giving the largest orbital energy variation from reactants to products. Reactions are taken to be electron transfer-driven when they provide small...

This report briefly describes the development and applications of net-sign graph theory. The current work enunciates the graph (molecule) signature of nonalternant non-benzenoid hydrocarbons with odd member of rings (non-bipartite molecular graphs) based on chemical signed graph theory. Experimental evidences and Hückel spectrum reveal that structure possessing nonbonding molecular orbital (NBM...

In a typical solitonic distribution, the soliton density is distributed over the entire moleculeand the present work shows how its density can be decomposed into solitonic and antisolitoniccomponents. It is found that there exists a unique electron as soliton over the anionicnanoconductor, while there are many other solitons and antisolitons. The solitonic states are furtherdecomposed to the ca...

In this study, spectroscopic properties of the single-walled boron-nitride nanotube (SWBNNT) –a semiconductor channel in molecular diodes and molecular transistors–have been investigated under field-free and various applied electric fields by first principle methods.Our analysis shows that increasing the electric field in boron-nitride nanotube (BNNT) decreases the Highest Occupied Crystal Orbi...

excited-sta,te charge distribution venting such a conformation. Extended Huckel calculations confirm this assumption. The potential energy curves for the rotation of the aldehyde group away from the plane of the phenyl ring for the ground state and the excited state of benzaldehyde arising from the carbonyl (n,n*) transition are shown in Figure 7. The calculated barrier to rotation is 0.22 eV f...