On October 11, Xueqing Gong, full professor in the East China University of Science and Technology and the recipient of National Science Fund for Distinguished Young Scholars, has visited our group by invitation and given a presentation on his recent work. He is prominent in catalysis and surface science by means of theoretical simulations. His talk firstly covered the behavior of various polarons on the CeO₂ surfaces (by oxygen vacancies or by supported Au clusters) from their density functional theory (DFT) calculations, and then mentioned their recent investigation on the surface reconstruction of Ti(011) surfaces in combination of generic algorithm in USPEX and DFT calculations. After the presentation, he conversed actively with the audience on various related topics.