Electron correlation is an important phenomenon to understand the properties of molecular and solid-state systems and is often dubbed nature’s “chemical glue”.

In a recent paper for the *Journal of Chemical Theory and Calculation*, we review electron correlation to help scientists better understand this complex field. The paper summarises the existing literature in a way that is more transparent, hopefully as a precursor to help researchers identify better use cases for quantum computers.

Most molecular calculations start from a simple model in which the electrons don’t really know exactly where the other ones are. The error this ‘blindness’ causes in energy calculations is called the correlation energy. The rule of thumb is that the larger the correlation energy is, the more likely that quantum computers will be useful.

The article is a review about how people calculate this electron correlation and what factors influence its magnitude. Based on that, it seems that strong correlation effects are more likely in solids than in molecules, and so solid states seem to be a better candidate for quantum benefit, although molecules are not fully excluded either.

You can read the full paper here.