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Confinement is a very common phenomenon in chemistry, for example, when molecules are located inside cavities. In these conditions, the electronic structure of atoms and molecules is modified. These changes could be mapped through the interaction with other molecules since non-covalent interactions between molecules are also influenced by confinement. In this work we address both topics, non-covalent interactions, and confined systems, using quantum chemistry tools with new software, emphasizing the importance of analyzing both fields simultaneously. [ABSTRACT FROM AUTHOR]

Three systems with different hydrogen bond strengths were examined by using the Hartree-Fock (HF), Kohn-Sham (KS) methods as well as the second-order Mollet-Plesset perturbation theory (MP2). Since the MP2 method used both, occupied and unoccupied HF orbitals, to compute the total energy, the contribution of the basis set superposition error (BSSE) was found to be bigger than that obtained with HF or KS methodologies.

It is for the first time that orientational probability distribution function for CO transiently docked in myoglobin (Mb) and Hb is established. The ordered protein structure around the active site of the enzyme has a selectivity even for small ligands.

Peptide nano-doughnuts were treated from synthetic peptides and organic Au salts through self-assembly. This may allow them to be applied on the fields of controlled release systems and during delivery.

A versatile procedure to synthesize mono disperse hollow polymer colloid particles which can self-assemble into a crystalline colloidal array (CCA) is developed. These help in confining the reaction inside the hollow particles to fabricate.

The existence of a set of structural criteria for the rational design of molecular receptors which complex NO(sub 3)(super -) anion due to hydrogen bonding interactions. recent research shows that it is possible to chelate three nonconnected urea groups to NO(sub 3)(super -), without any steric effects.

Deformations of the three most common cyclodextrins (α, β, and γ) were induced to form inclusion compounds with sertraline and abacavir. The deformations were obtained from classical molecular dynamics (CMD) using as starting point X‐ray structures. The molecular dynamics were performed in two ways, over the cyclodextrins with and without the presence of a guest. Two characteristic rings within these cyclodextrins were used to measure the distortions observed along with the molecular dynamics. A docking approach was used to build inclusion compounds over the structures obtained from CMD without the presence of sertraline or abacavir. Thus, we compared structures of inclusion compounds obtained from deformations induced by the presence of a guest or with intrinsic deformations exhibited by each cyclodextrin. After this step, each structure was optimized by the PBE0‐D3/6‐31G(d,p) method, and the electron density delivered by this method was used to perform the quantum theory of atoms in molecules approach to analyze intermolecular contacts between sertraline, or abacavir, and three cyclodextrins. From this procedure, we found that inclusion compounds obtained from X‐ray structures present the highest energies over the potential energy surface. Thus, for getting low‐lying energy structures of inclusion compounds, deformations on cyclodextrins are necessary. [ABSTRACT FROM AUTHOR]