Organic solvents are still used frequently in the chemical industry. For health and environmental reasons there is a strong tendency to develop ‘greener’ replacements. We study binary systems, of which the separate building blocks are typically solid at room temperature, but that become liquid upon mixing. Such systems are characterized by an eutectic point. We focus on studying and understanding the phase behaviour of such systems and relate this to the molecular structures involved. This offers fundamental insights that form the basis for applications of such solvents.