The study looked at how different types of coal affect how they break down when heated. They used coal samples with varying levels of maturity and density. By analyzing the coal's behavior under heat, they found that certain components in the coal interacted to create a system similar to a suspension. This interaction led to the formation of new, larger molecules. The researchers also found that the quality of the coal varied not just based on its properties, but also on how different components interacted with each other.