On September 28^th, professor Yanming MA from Jilin University was invited to the 35^th Science Lecture of College of Science. He delivered a talk themed “Crystal Structure Prediction Method and Computational Software”, which was chaired by prof. Zhang Wenqing, Dept. of Physics.

Prof. Yanming MA

Guest Introduction

Yanming MA, professor in physics and dean of College of Science, Jilin University, has long been engaged in the research of high-pressure physics and computational physics. He discovered the reverse Wilson transformation of sodium from metal to insulator under high pressure, and developed a crystal structure prediction method and computational software named CALYPSO, which has been applied by more than 2900 scholars in 70 countries. He was an awardee of National Science Fund for Distinguished Young Scholars, the China Youth Science and Technology Award. Dr.Ma is also an internationally recognized scientists and won the Jamieson Award from International High-pressure Science and Technology Association and the Walter Kohn Award from the Italian Center for Theoretical Physics.

His research group mainly focuses on the theoretical and experimental research on the new structure, phenomenon and effect of condensed matters under high pressure confinement condition, and the theoretical design and experimental integration of new functional materials under high pressure.

Lecture Review

Crystal structure is an important part in material research. Although the approach in determining crystal structure with X-ray diffraction has been developed, the purity, experiment conditions and the structural complexity still bring many challenges to the work.

During the report, prof. MA introduced the crystal structure prediction software named CALYPSO (Crystal Structural AnaLYsis by Particle Swarm Optimization), which was developed independently by his group.

Prof.MA is delivering the lecture

What they proposed is theoretical calculation-led crystal structure research, and the target is to determine the lowest energy state of the Born-Oppenheimer energy surface. Due to the high dimension and multiple low points of energy surface, the deciphering of its lowest energy state has become an NP-hard issue in mathematics and recognized as an unresolvable work. By applying the heuristic algorithm based on physical constraints and the category-based retrieval approach, prof.MA’s group simplifies the energy surface by integrating multiple target optimization of particle groups and decompose it by referring to the boding matrix quantification features. Today, CALYPSO has been widely adopted around the world in analyzing crystal structure.

Students are listening to the lecture

During the lecture, prof.MA also introduced typical applications of CALYPSO, for example,reducing the difficulty in producing chemical compound with Au-H, explaining the decrease of xenon in air, the structural phase of high-pressure materials. Besides the three-dimensional crystal structure research, CALYPSO could also help with the two-dimension layered material research and the two-dimension surface restructuring research,it also shows the potential of being applied into other hotspot researches.

Interaction

In the second section, the audience exchanged with prof. MA on the calculation principle and decomposition of energy surface, and Prof. Jiaqing HE, dean of College of Science and head of Dept. of Physics handed an honorary certificate to him.

Interaction

A group photo with Prof. Wenqing ZHANG and Prof. Jiaqing HE