Aromaticity is a property of cyclic (ring-shaped), planar (flat) structures with π bonds in resonance (those containing delocalized electrons) that gives increased stability compared to other geometric or connective arrangements with the same set of atoms. Aromatic rings are very stable and do not break apart easily. An aromatic ring contains a set of covalently […]
Since the discovery of graphene, a wide diversity of atomic-layer-thick, two-dimensional (2D) materials with varied properties have emerged. Of particular interest are those that exhibit semiconducting behaviour, such as hexagonal boron nitride (hBN). hBN is isoelectronic to graphene and has also a honeycomb lattice formed by alternating nitrogen and boron atoms, but in contrast to […]
Over the past several decades researchers have thought how materials and device architectures can efficiently convert solar radiation into electrical power through the photovoltaic effect. Those efforts have led to different methods and processes to produce green energy. In this context, organic photovoltaic (OPV) technology has received considerable attention because it indeed constitutes a new […]
Deoxyribonucleic acid (DNA) is the genetic material of most living organisms, being a major constituent of the chromosomes within the cell nucleus and playing a central role in the determination of hereditary characteristics by controlling protein synthesis in cells. DNA is, thus, a nucleic acid composed of two chains of nucleotides in which there is […]
Specialisation has necessarily led to the fragmentation of knowledge, creating loosely connected disciplines in which discoveries in one area are hardly known in others. This implies that the flow of knowledge is severely restricted among disciplines or even among different areas within the same discipline. In recent decades, different approaches have been proposed to overcome […]
Tetrapyrroles,“the pigments of life”,are key molecules for the metabolism of living organisms, supporting functions of vital importance such as electron transport, light-harvesting and oxygen reduction. Within this family of compounds, porphyrins are organic pigments characterized by the possesion of a cyclic group of four linked nitrogen-containing rings called porphyrin, the nitrogen atoms of which are […]
It is very difficult to obtain exact solutions to systems involving interactions between more than two bodies, using either classical mechanics or quantum mechanics. To understand the physics of many-body systems, it is necessary to make use of approximation techniques or model systems that capture the essential physics of the problem. T he complexity of […]
A nanoantenna with balanced electric and magnetic dipole moments exhibits a directive radiation pattern with zero backscattering. This is known as the first Kerker condition after Kerker, Wang, and Giles, who predicted in 1983 that, under plane wave illumination, magnetic spheres with equal relative permittivity and permeability radiate no light in the backscattering direction. They […]
The common understanding of the uncertainty relation says that it is impossible to measure both the position and the momentum of a subatomic particle, in the same instant to unlimited accuracy. The more accurate is the measurement of the momentum, the less accurate is the measurement of the position in that instant, and vice versa […]
Common glass, used in windows or bottles, for example, is made by heating a mixture of calcium oxide (lime), sodium carbonate (soda), and silicon (IV) oxide (sand), resulting in a calcium silicate. This silicate is not a crystal but a solid in which atoms are random and have no long-range ordered pattern. These kind of […]