Describing a Strongly Correlated Model System with Density Functional Theory

作者：Kong Jing^*; Proynov Emil; Yu Jianguo; Pachter Ruth

来源：Journal of Physical Chemistry Letters, 2017, 8(13): 3142-3146.

DOI：10.1021/acs.jpclett.7b01056

The linear chain of hydrogen atoms, a basic prototype for the transition from a metal to Mott insulator, is studied with a recent density functional theory model functional for nondynamic and strong correlation. The computed cohesive energy curve for the transition agrees well with accurate literature results. The variation of the electronic structure in this transition is characterized with a density functional descriptor that yields the atomic population of effectively localized electrons. These new methods are also applied to the study of the Peierls dimerization of the stretched even-spaced Mott insulator to a chain of H-2 molecules, a different insulator. The transitions among the two insulating states and the metallic state of the hydrogen chain system are depicted in a semiquantitative phase diagram. Overall, we demonstrate the capability of studying strongly correlated materials with a mean-field model at the fundamental level, in contrast to the general pessimistic view on such a feasibility.

• 出版日期2017-7-6