Perovskite is a kind of structure with scientific importance. As the silicates with perovskite structure are the main mineral components in the Earth’s lower mantle, the ABO3 transition metal oxide perovskites are the important research objects of physics and material sciences due to their subtle interactions between the 3d electronic spin, orbital, charge and crystal lattice which induce the unique physical and chemical properties. With the dense structure, when the outside environment (temperature, pressure) changes, perovskite adjusts its structure by the distortion, rotation and tilt of the coordinated BO6 octahedrons in their co-corner locations, and furthermore, even changes its symmetry leading a phase transition. In normal, such a phase transition does not show an obvious non-continuous change in their bonding length, therefore, without a marvelous change on the volume. However, the abnormal large volume collapse exists in the pressure induced phase transition in PbCrO3 cubic perovskite, which might produced by a special physical mechanism, will challenge the conventional wisdom on the phase transition of perovskite in general, and concurrently opening up a completely new group of perovskites with a very different structural behavior under pressures.

The Earth’s interior is a huge natural high-pressure and high-temperature system. The pressure, as a basic thermodynamic parameter, plays an important role on reducing the distances between atoms, increasing the overlap from neighboring electrons, modulating the crystal structure, electronic structure and the reactions among various atoms, producing a total new material. The combination between the DAC, synchrotron radiation and microscopic laser heating technologies is now the major tool to study the structural change at high pressures and the states of matters in the Earth interior. The DAC high pressure group in the Guangzhou Institute of Geochemistry headed by Dr. W. Xiao focuses on the research of the synthesis and phase transitions of natural minerals and related compounds under high-pressure and high-temperature conditions, especially on the research about the series of Earth’s deep materials and perovskites. In the process, they have a long time corporation with several synchrotron high pressure beam lines around the world, especially with high pressure station in Beijing synchrotron radiation facility (BSRF).