The solid solutions of chlorapatite compounds Ba₅Mn₃−[subscript]xV[subscript]xO₁₂Cl (x = 0–3.0) and Ba₅Mn₃−[subscript]xP[subscript]xO₁₂Cl (x = 0–3.0) have been synthesized through solid state reactions and Pechini or sol–gel method using citric acid. The colors of the samples change from white (x = 3.0) through turquoise (x = 1.5) to dark green (x...
The discovery of a brilliant-blue color upon the introduction of Mn³⁺
to the trigonal-bipyramidal (TBP) sites in YInO₃ has led to a search for other hosts
for Mn³⁺ in TBP coordination. An obvious choice would be YAlO₃. This compound,
which has only been prepared through a citrate precursor route, has...
A new compound Na3LiFeSbO6 has been synthesized by conventional solid state methods and
investigated using X-ray diffraction, DC magnetic susceptibility, 57Fe Mössbauer spectroscopy
and optical measurements. This compound crystallizes in a monoclinic unit cell and is related
to a family of honeycomb ordered layered oxide materials where Na+ fills octahedral...
From DFT based calculations establishing energy-volume equations of state, a proposition of high pressure candidate structures with reduced volumes, namely columbite and trirutile are proposed for fordite mineral SnNb₂O₆. The key effect is the destabilization of divalent tin in fordite towards tetravalent state upon compression. This is helped with smaller...
A complete solid solution between the anion-deficient pyrochlore Ag₂Sb₂O₆ and the ideal pyrochlore Cd₂Sb₂O₇ has been synthesized through the standard solid state ceramic method. Each composition has been characterized by various different techniques, including powder X-ray diffraction, optical spectroscopy, electron paramagnetic resonance and ¹²¹Sb Mössbauer spectroscopy. Computational methods based on...
The solid solution of In₂Fe₂₋ₓGaₓCuO₇ (space group P6₃/mmc) was synthesized and investigated through X-ray diffraction and magnetic susceptibility studies. Limited changes to the lattice parameters were observed as a result of the similar ionic radii for Fe³⁺ and Ga³⁺ in the trigonal bipyramidal (TBP) crystallographic site. An increase in the...
Hexagonal AMO₂ and AMO₃ phases have the same basic structure, and intermediate compositions for this structure have been prepared by topotactic oxidation of AMO₂ phases such as RCuO₂, where R is a trivalent rare earth cation. We now find that such intermediate phases can also be prepared by topotactic reduction...
Complete solid solutions with the composition Na₃M₂₋ₓM’ₓSbO₆ where M, M’ = Cu, Mg, Ni, Zn have been synthesized by conventional solid state techniques and were investigated using X-ray diffraction, magnetism and optical measurements. All compositions crystallize in a monoclinic unit cell and exhibit a layered structure with a honeycomb cationic...
The solid solutions of InGa₁₋ₓFeₓCuO₄, InFeCu₁₋ₓMgₓO₄, and InGa₁₋ₓFeₓCu₁₋ₓMgₓO₄ were
synthesized and characterized through the use of X – ray and neutron diffraction, and DC –
magnetism measurements. All compositions of InGa₁₋ₓFeₓCuO₄ are single phase and crystallize
in the R3m space group, but a transformation to the spinel InFeMgO₄ structure was...
Interstitially filled skutterudites are a promising class of state-of-the-art thermoelectric
materials. Although thermoelectrics are exposed to significant thermal stresses, little
information is known about the fracture toughness of interstitially doped skutterudites. This
work explores the fracture toughness of undoped Co₄Sb₁₂ and indium doped In₀.₁Co₄Sb₁₂
skutterudites using three methods: 1) Vickers...