-phase transition of elemental cerium metal.

The isostructural-phase transition in elemental cerium has been the subject of many experimental and theoretical studies over almost the past century without a universally agreed upon mechanism. Here, we report the results of an extensive study of electronic and magnetic structures,-electron number, entanglement entropy, and elastic properties of cerium in the GGA +framework. We have found that almost all changes in the studied quantities mimic their behavior in the phase transition and could be related to the symmetry of the 4occupation and the small change in Hubbardnear a critical value.

Ab initio study on the rare-earth iron-pnictides RFeAsO (R = Pr, Nd, Sm, Gd) in the low-temperature Cmma phase.

We present density functional theory calculations on the iron-based pnictides RFeAsO (R = Pr, Nd, Sm, Gd). The calculations have been carried out using plane waves and the projector augmented wave (PAW) pseudopotential approach. Structural, magnetic and electronic properties are studied within the generalized gradient approximation (GGA) and also within GGA + U in order to investigate the influence of electron correlation effects.