A cement is any of various substances used for bonding or setting to a hard material. A popular one, Portland cement, is a mixture of calcium silicates and aluminates made by heating limestone (CaCO3) with clay (that contains aluminosilicates) in a kiln. The product is then ground to a fine powder. When Portland cement is […]
People might once have considered oxygen a human right. But the pandemic has revealed that access to oxygen – in a pure form, for medical use – is a luxury in most low and middle-income countries. Getting access to pure oxygen for medical treatments is a complicated, expensive and often very dangerous business. The current […]
Molecules when excited from their ground state (S0) to their lowest electronically excited states often change their electronic structure considerably, which impacts on a range of important molecular properties. For example, the reactivity of a molecule in its excited state often differs markedly from that in its S0 state. Also, the charge distribution within a […]
You are surely familiar with the concept that light behaves like electromagnetic radiation, and that it responds to the equation In this way, the higher the wavelength of the light, the lower its frequency, and vice versa. This means that if we compare red and blue light, for example, we will see that red light […]
In spintronics, new memory and logic devices are being developed based on the use of spins of nuclei, atoms, or molecules, instead of electronic charges. The main advantages are an improved energy efficiency and speed of operation to store and process information. The ability of organic molecules to maintain magnetic multistability in nanoscale junctions will […]
Adsorption commonly is understood as the reversible binding of molecules and atoms from the gaseous or liquid phase on surfaces, mostly of highly porous adsorbent media. In chemisorption a single layer of molecules, atoms or ions is attached to the adsorbent surface by chemical bonds; in physisorption only van der Waals forces are involved. Adsorption […]
Organic-based materials have gained rising interest as active components in electronics, energy conversion and catalytic systems. However, the discrete nature of the molecular constituents of these systems implies a reduced electron conductance, lowering the device efficiency. In order to increase the electron delocalization through an improved structural order, which favors orbital overlap and consequently the […]
Auranofin is a gold (Au) salt classified by the World Health Organization as an antirheumatic agent. It was approved for the treatment of rheumatoid arthritis in 1985, but is no longer a first-line treatment due to its adverse effects on a long-term basis. But the drug is important in another way. The discovery that auranofin […]
Carbon monoxide (CO) oxidation (2CO + O2 → CO2) on platinum (Pt) group metal surfaces is the model heterogeneous gas/surface catalytic reaction. Pt itself is of the upmost importance as a catalyst for car exhaust cleaning or for the water gas shift reaction, whereas Pt crystal surfaces are model systems for investigating the catalytic CO […]
The magnitude of many of the exotic phenomena predicted for topological semimetals is directly proportional to something called the Chern number. Given the importance of the Chern number magnitude for these phenomena, it is just natural to wonder whether there is an upper limit for it and whether there are real materials in which this […]
