Planar pyrochlore: A valence-bond crystal

Bond softness sensitive bond-valence parameters for crystal structure plausibility tests

Based on a description of bond valence as a function of valence electron density, a systematic bond softness sensitive approach to determine bond-valence parameters and related quantities such as coordination numbers is elaborated and applied to determine bond-valence parameters for 706 cation-anion pairs. While the approach is closely related to the earlier softBV parameter set, the new softNC...

Ni2As2O7 pyrochlore nanomaterial: Solid state synthesis, crystal structure determination, crystal phase growth study and physical properties

Nanostructured Ni2As2O7 semiconductor samples were synthesized by a solid state method among As2O3 and Ni(NO3)2.6H2O raw materials at 650 °C (S1) and 750 °C (S2) as reaction temperatures. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique and F...

The planar pyrochlore antiferromagnet: A large-N analysis

We study possible quantum phases of the Heisenberg antiferromagnet on the planar pyrochlore lattice, also known as the checkerboard lattice or the square lattice with crossings. It is assumed that the exchange coupling on the square-lattice-links is not necessarily the same as those along the crossing links. When all the couplings are the same, this model may be regarded as a two dimensional an...

Ni2As2O7 pyrochlore nanomaterial: Solid state synthesis, crystal structure determination, crystal phase growth study and physical properties

Nanostructured Ni2As2O7 semiconductor samples were synthesized by a solid state method among As2O3 and Ni(NO3)2.6H2O raw materials at 650 °C (S1) and 750 °C (S2) as reaction temperatures. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique and F...

A chemist's guide to valence bond theory