Crystal-structure refinement of Sr3Ga2Ge4O14

摘要: The accurate X-ray diffraction study of a Sr3Ga2Ge4O14 crystal was performed based on two data sets collected diffractometer equipped with CCD area detector (a = 8.2776(2), c 5.0415(1) A, sp. gr. P321, Z 1, R/wR 0.78/0.69%, 3645 independent reflections). structure is characterized by the presence mixed cation sites, which accompanied anharmonic motion not only cations, but also oxygen atoms in general positions. structures and electromechanical characteristics Sr3TaGa3Si2O14 were compared. larger elongation Sr polyhedron along axis and, simultaneously, smaller unit-cell parameter compared Sr3TaGa3Si2O14, correlates ratio piezoelectric coefficients d11. absence thermally stable directions crystals consistent anomalous temperature dependence dielectric constant ɛ33.