Water is a very common substance on the earth, but from a chemical point of view, its characteristics are extremely abnormal.For example, most substances shrink in volume when cooled, but water below 4 ° C expands and loses density when cooled.Molecules are randomly arranged and oriented in liquid water, whereas in ice, the arrangement is fixed and there are gaps between the molecules because they point in a fixed direction.In addition, water usually begins to freeze at 0 ° C, but there is also a state of supercooling that does not freeze even below that temperature.Water continues to expand even in a supercooled state, but what the molecules look like has been a long-standing mystery.In this state, it has an intermediate density between normal liquid water and ice, so it was thought that it might be an array of ice-like molecules.On the other hand, it is hard to think that a liquid and a solid are in exactly the same state.

　The group used computer simulations to analyze the state of the molecules in the supercooled water.As a result, it was found that several molecules gathered to form a lump to reduce the density, and the lump freely moved to maintain its fluidity as a liquid.Since this is a simulation result, it is hoped that such a mass of water molecules will be actually observed by experiments.

　Water is a substance that has many properties that can be said to be abnormal, and is full of unexpectedly unknown properties.Life that has lived using water has lived using the anomaly of water.Many of the unexplained mysteries of life may be derived from the mystery of water.Understanding water will also lead to understanding of life.