Physicists create first computer model of long theorized ideal glass

Yesterday 08:50

By: Dakir Madiha

Physicists create first computer model of long theorized ideal glass

Physicists at the University of Oregon have produced the first computer model of an “ideal glass,” a theoretical form of matter in which molecules are packed as tightly and stably as possible while still maintaining the disordered structure typical of glass. The achievement, reported in Physical Review Letters, addresses a scientific challenge first proposed nearly 80 years ago and could reshape future approaches to designing advanced materials.

The research team, led by physicist Eric Corwin, tackled a problem that dates back to 1948 when Princeton chemist Walter Kauzmann suggested that a glass cooled to extremely low temperatures might eventually reach a perfectly stable state. In this hypothetical state, molecules remain arranged randomly but are packed so efficiently that the material behaves mechanically like a crystal.

Despite decades of study, scientists had never observed or reproduced such a structure, even in simulations. Instead of attempting to mimic the slow cooling process typically used to study glass formation, the Oregon team constructed the material directly through computational modeling using the university’s high performance computing cluster.

Corwin said the group pursued a different approach by building the optimal molecular arrangement from the start. By constructing the structure directly, the researchers were able to explore a configuration that conventional cooling simulations could not reach.

The model began with two dimensional arrangements of disk shaped molecules. Researchers drew inspiration from the honeycomb geometry found in crystals, where each disk touches six neighbors. They then developed a method to preserve the dense packing while removing repeating crystalline order, creating a fully amorphous structure that nonetheless behaves mechanically like a crystal.

According to Corwin, the resulting configuration displays the same mechanical response as crystalline materials despite lacking an ordered lattice.

The simulated structures also showed the key properties long predicted for ideal glass. These include unusually high compressibility and shear moduli, extremely high density, and zero configurational entropy. The model also avoided the low frequency vibrations normally seen in amorphous materials and demonstrated a phenomenon known as hyperuniformity, where structural fluctuations remain highly constrained across large scales.

Researchers say the findings could have practical implications for materials science, particularly in the development of metallic glasses. These metals possess disordered atomic structures that make them strong and resistant to deformation, but they are difficult to manufacture because they require extremely rapid cooling.

A better understanding of ideal glass could allow engineers to design alloys that form glassy states more easily. That breakthrough could enable complex parts to be manufactured through casting instead of machining.

Corwin said the potential applications could be transformative. If materials with ideal glass properties can be realized experimentally, engineers might one day cast complex components such as automobile engines or aircraft structures directly from molds.

The team now plans to extend the research into three dimensional systems. However, the computational methods used in the current study cannot yet be applied directly to fully three dimensional models, meaning additional theoretical advances will be required.