3 papers
cond-mat.mtrl-sci2002
Polarization and Structure of Small Clusters
W. Geertsma
In this paper we report the structure of the Li4Ge4 cluster as a function of charge transfer and polarizability. We find that for small charge transfer (Q < 0.5) this cluster has t…
cond-mat.mtrl-sci2002
Polarization and Covalency in Alkali-Tetralide Clusters
Wiebe Geertsma
In this paper we discuss the structure of A4M4 alkali(=A)- tetralide (= M) (= group 14) clusters. Without polarization these polyions consist of a central tetralide tetrahedron wit…
cond-mat.str-el2002
Spin order on pyrochlore lattices studied by the Self-Consistent Cluster Approach
Wiebe Geertsma
In this paper we present a study of magnetic order of quantum Heisenberg spins on pyrochlore type lattices: a lattice of corner sharing tetrahedra. We use the Cluster Variation App…