What is magnetic superexchange and double-exchange?

However, in superexchange, a ferromagnetic or antiferromagnetic alignment occurs between two atoms with the same valence (number of electrons); while in double-exchange, the interaction occurs only when one atom has an extra electron compared to the other.

What is magnetic exchange coupling?

➢ Magnetic Exchange Coupling Magnetically dilute substances simply refer to the magnetic materials in which individual paramagnetic centers cannot interact with each other due to a large distance of separation.

What is antiferromagnetic interaction?

In antiferromagnetic materials, which include certain metals and alloys in addition to some ionic solids, the magnetism from magnetic atoms or ions oriented in one direction is canceled out by the set of magnetic atoms or ions that are aligned in the reverse direction.

What is double-exchange interaction?

As we known, the double-exchange (DE) is a type of a magnetic interaction between two transition metal ions via oxygen ions. The ability to hop, or to localized, reduces the kinetic energy, hence the overall energy saving can lead to ferromagnetic (FM) alignment of the neighboring transition metal ions.

Which is more common exchange coupling or superexchange?

This type of exchange coupling is actually very unusual. The more common form of magnetic exchange in an insulating material is superexchange – this is where the electrons on a magnetic atom interact with electrons on another magnetic atom, by way of the electronic orbitals of a non magnetic atom bonded in between.

How does exchange coupling explain the direction of magnetism?

This means that we can describe the magnetic atom as a tiny bar magnet, and we usually represent this by drawing an arrow through the atom, to show the direction of the magnetism (we call this the magnetic moment). Exchange coupling is the way in which two magnetic atoms (or ions) in a material interact with each other.

How is the superexchange different from direct exchange?

Superexchange (or Kramers–Anderson superexchange) is the strong (usually) antiferromagnetic coupling between two next-to-nearest neighbour cations through a non-magnetic anion. In this way, it differs from direct exchange in which there is coupling between nearest neighbor cations not involving an intermediary anion.

How does the superexchange interaction cause spontaneous magnetization?

This spontaneous magnetization is due to the ordering influence of the neighboring spins viz. exchange interaction. This interaction tends to align spins parallel or antiparallel depending on crystal structure. What is the influence of the superexchange phenomenon?