-We have investigated the influence of charge on the ground state structures for small Sin (n=5-10) clusters by using the full-potential linear muffin-tin orbital molecular-dynamics (FP-LMTO-MD) method. Addition or removal of one or two electrons does not change the geometrical configurations of the small Sin (n=5-10) clusters even though they undergo some structural distortion. But the structu...

Quantum-chemical computations of solids benefit enormously from numerically efficient plane-wave (PW) basis sets, and together with the projector augmented-wave (PAW) method, the latter have risen to one of the predominant standards in computational solid-state sciences. Despite their advantages, plane waves lack local information, which makes the interpretation of local densities-of-states (DO...

Qualitative molecular orbital theory is central to our understanding of the bonding and reactivity of molecules and materials across chemistry. Advances in computational technology and methodology, however, have made ab initio or density functional theory calculations a simpler alternative, offering reliable results on increasingly large systems in a reasonable time-scale without the need for c...

Molecular Dynamics (MD) simulation and Density Functional Theory (DFT) methods have been used to evaluate the efficiency of four quinoline derivatives on corrosion inhibition in the aqueous phase. Some quantum chemical parameters such as hardness (η), electrophilicity (w), polarizability (a), energy of the highest occupied molecular orbital (EHOMO), energy of th...

Among all the Quantum Mechanics/Molecular Mechanics (QM/MM) methods available to describe large molecular systems, the Local Self-Consistent Field/MM (LSCF/MM) one uses frozen doubly occupied Strictly Localized Bonding Orbital (SLBO) to connect the QM fragment to the one treated at the MM level. This approach is correct as long as the QM part is large enough to minimize the artifacts that could...

Nine AuX molecules (X = H, O, S, Se, Te, F, Cl, Br, I), their isoelectronic HgX analogues, and the corresponding neutral HgX diatomics have been investigated using NESC (Normalized Elimination of the Small Component) and B3LYP theory to determine relativistic effects for bond dissociation energies (BDEs), bond lengths, dipole moments, and charge distributions. Relativistic effects are substanti...

ZnO has been extensively studied by virtue of its remarkably high piezoelectric responses, especially in nanowire forms. Currently, the high piezoelectricity of wurtzite ZnO is understood in terms of the covalent-bonding interaction between Zn 3d and O 2p orbitals. However, the Zn 3d orbitals are not capable of forming hybridized orbitals with the O 2pz orbitals since the Zn ion is characterize...

Despite the burgeoning field of uranium-ligand multiple bonds, analogous complexes involving other actinides remain scarce. For thorium, under ambient conditions only a few multiple bonds to carbon, nitrogen, oxygen, sulfur, selenium and tellurium are reported, and no multiple bonds to phosphorus are known, reflecting a general paucity of synthetic methodologies and also problems associated wit...

A series of naphthyl-bridged amino-borane derivatives, namely 1-(dimethylamino)-8-naphthylboranes (1, 3, 5, 7) and 5-(dimethylamino)-6-acenaphthylboranes (2, 4, 6, 8, 10, 11), differing in the steric and electronic properties of the boryl moiety, have been synthesized and fully characterized by spectroscopic and crystallographic means. Structural X-ray analysis of the peri-atom displacement and...

In the light of computational chemistry, based on morpholinium cation-based Ionic Liquid, their different types of physical, chemical, and biological properties is highlighted. The physical properties are evaluated through the Density Functional Theory (DFT) of Molecular Mechanics and also examine the chemical and biological properties. The difference between Highest Occupied Molecular Orbital ...