XU Guangxian, chemist, was born in Shaoxing, Zhejiang Province in November 1920. In 1951, he received his Ph.D. from Columbia University in US. He was elected a CAS Member in 1980. He serves as a vice editor-chief of Science in China and Chinese Science Bulletin. He has long been engaged in teaching and research in physical chemistry and inorganic chemistry which involves the fields of quantum chemistry, chemical bond theory, coordination chemistry, extraction chemistry, nuclear fuel chemistry and rare-earth science, etc. By summarizing a large number of literatures, he put forward the new concept of nxc XU Guangxian, chemist, was born in Shaoxing, Zhejiang Province in November 1920. In 1951, he received his Ph.D. from Columbia University in US. He was elected a CAS Member in 1980. He serves as a vice editor-chief of Science in China and Chinese Science Bulletin. He has long been engaged in teaching and research in physical chemistry and inorganic chemistry which involves the fields of quantum chemistry, chemical bond theory, coordination chemistry, extraction chemistry, nuclear fuel chemistry and rare-earth science, etc. By summarizing a large number of literatures, he put forward the new concept of nxc