New Members of the (Ba_8Co_6O_(18))_(#alpha#)(Ba_8Co_8O_(24))_(#beta#)Polysomatic Series

摘要

The accurate control of both stocihiometry and synthsis condition has allowed th stabilization of new Ba-Co oxides with one-dimensional structures relatd to the 2H-ABO_3 hexagonal perovskite. Ba_(26)Co_(23)O_(69), Ba_(44)Co_(39)O_(117),and Ba_(28)Co_(25)O_(75) are new members of the (Ba_8Co_6O_(18))_(#alpha#)(Ba_8Co_8O_(24))_(#beta#) polysomatic orthorhombic series whose structureal featural have been characterized by electron diffraction and high-resolution electron microscopy. These polysomers are described as the ordered intergrowth between structural slabs of one-half unit cell of the o-Ba_8Co_7O_(21) and one Ba_8Co_8O_(24) 2H-block in different ratios