The packing of atoms, molecules, and polymers in a given volume -either in crystalline or amorphous formis a fundamental and long-standing issue that has been considered by various disciplines for over a century . The packing density directly impacts properties such as the ionic conductivity , mobility in solvents , mechanical and optical behavior , as well as numerous other physical and chemical properties . Today, the packing density has gained renewed attention in the context of developing advanced materials that fulfill very specific property requirements. Molecular materials and polymers are of particular interest as their packing in the bulk is directly affected by their molecular structure . Manipulating and tailoring the latter offers many opportunities (and challenges) to achieve targeted density values.