A simple approximation for the Pauli potential for the groundstate of atomic systems is given, which in connection with Hohenberg-Kohn variational procedure yields selfconsistent electron densities exhibiting proper atomic shell structure.

Single crystals of the polytellurides RETe1.8 of gadolinium, terbium, and dysprosium were prepared by chemical vapor transport and alkali metal halide flux reactions. To determine proper synthesis conditions for the desired target composition, the binary phase diagram Gd‐Te was evaluated by CalPhaD methods. The compounds are isostructural to SmTe1.8 and crystallize in space group P4/n (no. 85) with lattice parameters of a = 966.10(4), 960.00(3), and 957.33(2) pm and c = 1794.15(10), 1785.77(6), and 1779.38(5) pm for GdTe1.8, TbTe1.8 and DyTe1.8, respectively. The structures consist of puckered [RETe] double slabs and planar telluride layers composed of Te2 dumbbells and linear Te3 units in accordance with ELI‐D based bonding analyses. The latter can be understood as a Te34– anion. GdTe1.8 is a semiconductor with a bandgap of 0.19 eV/0.17 eV (experimental/calculated). Magnetization data confirm trivalent RE ions and indicate antiferromagnetic order at TN = 12 K for TbTe1.8 and TN = 9.8 K for DyTe1.8, whereas GdTe1.8 remains paramagnetic down to 2 K.

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Beyond electronegativity and local hardness: Higher-order equalization criteria for determination of a groundstate electron density J. Chem. Phys. 129, 054111 (2008) The local conditions for the Pauli potential that are necessary in order to yield self-consistent electron densities from orbital-free calculations are investigated for approximations that are expressed with the help of a local position variable. It is shown that those local conditions also apply when the Pauli potential is given in terms of the electron density. An explicit formula for the Ne atom is given, preserving the local conditions during the iterative procedure. The resulting orbital-free electron density exhibits proper shell structure behavior and is in close agreement with the Kohn-Sham electron density. This study demonstrates that it is possible to obtain self-consistent orbital-free electron densities with proper atomic shell structure from simple one-point approximations for the Pauli potential at local density level. C 2016 AIP Publishing LLC. [http://dx

An orbital-free implementation of the original Hohenberg-Kohn theorems is presented, making use of the scaling properties from a fictitious Kohn-Sham system, but without reintroducing orbitals. The first order fragment approach does not contain data or parameters that are fitted to the final outcome of the molecular orbital-free calculation and thus represents a parameter-free implementation of orbital-free density functional theory, although it requires the precalculation of atomic data. Consequently, the proposed method is not limited to a specific type of molecule or chemical bonding. The different approximation levels arise from including (first order) or neglecting (zeroth order) the dependency between the potential and the electron density, which in the bifunctional approach are formally treated as independent variables.