Preface

Over the course of five years, energetic members from all over Japan worked together to pioneer new, multidisciplinary materials science.Although we've encountered difficulties in carrying out the project due to the global pandemic, we have overcome these through the collaborative efforts of our team.In our project, we utilized advanced quantum beams, synchrotron X-rays, neutrons and electrons in combination with computer simulations, advanced mathematics and informatics.One of our scientific objectives was to study nanostructures containing hetero-elemental dopants and vacancies, which latter can be considered as new elements not found in the periodic table.We believe that the freedom to combine and arrange dopants can generate novel functional properties.Another focus of the project was its application to disordered materials.Interpreting dopants in disordered materials is more challenging than in crystals, where they are categorized as either substitution or interstitial sites.This is because the atomic arrangement in disordered materials is inherently disordered, making it difficult to define such sites.In this project, therefore, we applied topological analysis to understand the hyperordered structure in terms of order within disorder.This provided us with crucial information about the functional properties of glasses.We are confident that hyperordered structures can exist in a wide range of materials, including dielectrics, functional glasses, zeolites, batteries, superconductors and biomaterials.These structures can be regarded as a treasure trove of material functionality.In this special issue, we have invited ten articles describing hyperordered structures in the aforementioned materials.We hope that this special issue will lead to new breakthroughs in materials science and strengthen Japan's scientific presence in the future.