Wenjian Liu got his Ph. D in 1995 at Peking University and then carried out 6-year postdoctoral researches in Germany. He was promoted to a full professor in the end of 2001. He has been working in the field of relativistic molecular quantum mechanics (RMQM) and has significantly advanced the machinery of relativistic theories and methods for molecular electronic structure and magnetic properties. He proposed an effective QED approach that bridges seamlessly relativistic quantum chemistry and QED, the two mutually exclusive subfields of RMQM. He also unified the two branches of no-pair relativistic methods, four- and two-component, by showing that they are fully equivalent in all the aspects of simplicity, accuracy and efficiency. The X2C (exact two-component) equation serves as a seamless bridge between the Dirac and Schrödinger equations. Furthermore Dr. Liu established the general framework for relativistic explicitly correlated wave function methods by introducing the concept of extended no-pair projection and the conditions of relativistic wave functions at the coalescence of two electrons. He proposed a novel four-component relativistic theory for NMR parameters, which has solved a 45-year longstanding issue concerning the `missing' diamagnetism in the Dirac picture and has meanwhile greatly simplified the computation by reducing the requirement on the basis set. He also proposed an exact two-component theory for magnetic properties, which is even simpler than the existing approximate ones. He introduced a general body-fixed relativistic molecular Hamiltonian for various molecular spectroscopies. Based on this Hamiltonian, the relativistic theory of nuclear spin-rotation (NSR) constant is formulated rigorously, 63 years after the non-relativistic counterpart. In particular, a `relativistic mapping' between experimental NSR and NMR is established, which is going to replace the `non-relativistic mapping' being used for more than 6 decade. Dr. Liu developed the ever first time-dependent four-component relativistic density functional theory (TD-DFT) and proposed the key concept of non-collinear exchange-correlation kernel to properly account for spin-orbit couplings in electronic excitations. In terms of such a kernel, the spin-dependent (four- and two-component) and spin-free (scalar relativistic and non-relativistic) versions of TD-DFT have been unified into a single matrix form. He formulated a spin-adapted TD-DFT for excited states of open-shell systems, which is far simpler than the previous ones. He also developed a linear scaling TD-DFT in the spirit of `from fragments to molecule', that can handle both local and charge transfer excitations of large systems composed of all kinds of chemical bonds. The underlying `bottom up localization' of global occupied and virtual orbitals is also a good candidate for wave-function-based local correlation/excitation. These developments are highly promising for first-principles studies of luminescent materials.
The above seminal works have rendered him a worldwide leading figure in the field of RMQM. Because of these achievements, he was awarded a number of distinguished prizes, including the annual medal of International Academy of Quantum Molecular Science, the Pople Medal of Asia-Pacific Association of Theoretical and Computational Chemists, and the Bessel Research Award of Alexander von Humboldt Foundation. He was elected to be the chairman for the 9th International Conference on Relativistic Effects in Heavy-Element Chemistry and Physics (Sept. 25-29, 2010, Beijing). He was invited as a guest editor to compose a special issue of Chemical Physics in memory of this Conference: Recent advances and applications of relativistic quantum chemistry, Vol. 395, 2012.