Author archives: DIPC

The importance of the dynamical electron-nuclear correlation terms

The importance of the dynamical electron-nuclear correlation terms

ChemistryCondensed matterPhysicsQuantum physics

By DIPC

Ionization is a fundamental process in chemistry and physics, lying at the heart of many fascinating phenomena. Ionization is the process of producing ions. Certain molecules ionize in solution, for example. But ions may also be formed when an atom or molecule loses one or more electrons as a result of energy gained in a […]

Introducing impurities

Introducing impurities

Condensed matterMaterialsPhysicsQuantum physics

By DIPC

The most extensive use of semiconductors, such as silicon or germanium, including their use as transistors, arises from their behavior when, after being sufficiently purified of atoms other than the basic element (e.g., silicon or germanium), very small amounts of special impurities are carefully introduced. While the methods for first purifying then adding small amounts […]

A working molecular electronic switch

A working molecular electronic switch

ChemistryComputer scienceCondensed matterMaterialsPhysics

By DIPC

A visionary perspective of molecular electronics is the use of single molecules as functional entities in electronic devices. In this context, some of the most important components are molecular switches, which are molecules that can be interconverted reversibly between at least two stable states, one for the OFF and one for the ON. In order […]

Semiconductors

Semiconductors

Condensed matterMaterialsPhysics

By DIPC

The most prevalent use today of semiconductors is forming them into transistors, the basic electronic building blocks of all “solid-state electronics” and computer microchips. Semiconductors are the most important materials in the burgeoning revolution in computers and other electronic devices today. Such applications also arose, beginning in the 1930s, from the quantum mechanics of the […]

Impurities and spin Hall effects in graphene

Impurities and spin Hall effects in graphene

Condensed matterMaterialsPhysicsQuantum physics

By DIPC

The interactions between moving charges and magnetic fields can be quite complicated; more if we consider the quantum effects. One example is the collection of Hall effects. There are analogues of these effects for spin and the detection of the most sophisticated one in graphene, where, at least, it should not be strong, is something […]

The complementarity principle

The complementarity principle

PhysicsQuantum physics

By DIPC

Quantum mechanics was founded upon the existence of the wave–particle dualism of light and matter, and the enormous success of quantum mechanics, including the probability interpretation, seems to reinforce the importance of this dualism. But how can a particle be thought of as “really” having wave properties? And how can a wave be thought of […]

Superconductivity and the BCS theory

Superconductivity and the BCS theory

Condensed matterPhysics

By DIPC

The band theory of metals has been subjected to experimental tests many times and is now the accepted model of the behaviour of conductors and insulators. But it has to be modified when it comes to superconductivity. Electrical resistance is due to collisions of the electrons (whether treated as particles or waves) with impurities, imperfections […]

All-metal aromatic compounds

All-metal aromatic compounds

ChemistryCondensed matter

By DIPC

In the early days of organic chemistry, the word aromatic was used to describe fragrant substances such as benzene (from coal distillate), benzaldehyde (from cherries, peaches, and almonds), and toluene (from tolu balsam). It was soon realized, however, that substances classed as aromatic differed from most other organic compounds in their chemical behaviour. Today, the […]

Why do some materials conduct electricity and others don’t? (2): The band theory of solids

Why do some materials conduct electricity and others don’t? (2): The band theory of solids

Condensed matterPhysics

By DIPC

In 1928, just two years after the formulation of quantum mechanics, the German physicist Arnold Sommerfeld modified the classical free-electron model by treating the electrons according to quantum mechanics. But the new theory still contained the unrealistic assumption that the electrons do not interact with the charged lattice ions except to collide with them. As […]