1. Quantum simulations in real materialsShiweiZhang, College of William and Mary, DMR 1006217 Possible high-density H-storage system? A model problem: Ca+-4 H2 Predictive electronic structure calculations are at the core of materials modeling. We are developing a new method, auxiliary-field quantum Monte Carlo (AFQMC), which can better treat electron interaction effects. AFQMC takes the form of random walks in mean-field space, and can be “easily” built on top of standard machineries in condensed matter and chemistry to improve accuracy.  From Bajdichet. al., PRB 82, 081405(R) (2010) AFQMC • Is there binding? If so, how does it vary with the bond length Z (see cartoon above)? For technical descriptions, see publications athttp://physics.wm.edu/~shiwei Collaborators: C.-C. Chang, S. Chiesa, H. Krakauer, F.J. Ma, W. Purwanto, H. Shi, E.J. Walter, Y. Virgus, J.Xu • State-of-the-art calculations with different methods gave different answers. • AFQMCallows accurate calculations; predicts double-well structure.

2. Quantum simulations in real materialsShiwei Zhang, College of William and Mary, DMR 1006217 • Curriculum development: course on Computer Simulations in Physics • Undergraduate year-long research and REU • - Recent Ph.D students and postdocs: Wissam Al-Saidi(now U. Pitt.); Chia-Chen Chang (now UC Davis); Simone Chiesa; Fengjie Ma; HendraKwee(Now professor in Indonesia);WirawanPurwanto; H. Shi; M. Cherry Suewattana(Now faculty at MahidolUniv); Dorothy J. Xu • Co-organizer and/or lecturer of several summer/winter schools “Matter show” – W&M Physics faculty members developed a highly popular set of demos to illustrate the state of matter, using liquid helium. The PI doing a “matter show” at a local elementary school. http://physics.wm.edu/~shiwei