2020 Volume 59 Issue 3 Pages 286-291
A new material concept of Soft Crystals is proposed. Soft Crystals respond to gentle stimuli such as vapor exposure and rubbing but maintain their structural order exhibiting remarkable visual changes in their shape, color, and luminescence. These crystals can be organic crystals, inorganic crystals, or inorganic-organic hybrid crystals (metal complex crystals) etc. In this article, several interesting examples of Soft Crystals, which exhibit vapochromic, mechanochromic, or superelastic phenomena, are introduced. These phenomena draw increasing attention for the scientific viewpoints of response systems with high structural order. In addition, Soft Crystals are expected to have potential application to visual sensing and finely controllable electronic devices. The newest topics can be seen in this special issue of Soft Crystals.