In school we are taught that there are two different kinds of chemical bonds that atoms can make; ionic bonds, where electrons from one atom are donated to another atoms, and covalent bonds, where electrons are shared between two atoms. The truth is that real chemical bonds are a mixture of both. When two atoms come together their atomic orbitals in the sub shells combine to form molecular orbitals. For every two atomic orbitals that collide, two molecular orbitals are created, one in a lower energy state than the other.

The lower energy state orbital is lower than either of the two original atomic orbitals and is known as the bonding orbital, by comparison the other molecular orbital is in a higher energy state than either of the atomic orbitals and is called the anti-bonding orbital. Where both orbitals have the same number of electrons in it, the difference between the anti-bonding orbital and the highest energy atomic orbital is greater than the difference between the bonding orbital and the lowest energy atomic orbital and so the bond wouldn’t form as both molecular orbitals would be in a higher energy state than the atomic orbitals from which it is formed. This is why atoms with full outer orbitals (the noble gases) don’t like to form molecular bonds here on earth. Maybe a diagram is in order:

The point of all this is that scientists in Norway have used computer simulations to model chemical bonds in the extreme magnetic fields of neutron stars and white dwarfs. They have found that a new type of chemical bond is formed at these extreme magnetic fields. The basis is that in these magnetic fields, the anti-bonding orbital can exist at a lower energy state than the highest energy atomic orbital. This means that the noble gases will be able to form new and interesting molecules of which the likes have never been seen on earth before. The only catch, and it’s a big one, is that the magnetic fields need to be in the region of 105 T which in much, much, much bigger than the measly 30-40T fields that we can muster here on earth at the minute. Ah well.

 

T. Gloess

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