title: Prediction of incommensurate crystal structure in Ca at high pressure.
abstract: Ca shows an interesting high-pressure phase transformation sequence, but, despite similar physical properties at high pressure and affinity in the electronic structure with its neighbors in the periodic table, no complex phase has been identified for Ca so far. We predict an incommensurate high-pressure phase of Ca from first principle calculations and describe a procedure of estimating incommensurate structure parameters by means of electronic structure calculations for periodic crystals. Thus, by using the ab initio technique for periodic structures, one can get not only reliable information about the electronic structure and structural parameters of an incommensurate phase, but also identify and predict such phases in new elements.
authors.affiliation: Department of Physics and Materials Science, Condensed Matter Theory Group, Uppsala University, Box 530, S-751 21 Uppsala, Sweden.
authors.forename: Sergiu
authors.initials: S
authors.lastname: Arapan
authors.forename: Ho-Kwang
authors.initials: HK
authors.lastname: Mao
authors.forename: Rajeev
authors.initials: R
authors.lastname: Ahuja