Ideal n=3 phase Ca4Mn3O10 of Ruddlesden-Popper series obtained using high pressure and high temperature

An ideal n=3 member of Ruddlesden-Popper (RP) phase Ca4Mn3O10 was obtained by solid-state reaction under high pressure. This phase has been studied by transmission electron microscopy, convergent beam electron microscopy, hig h-resolution transmission electron microscopy, and electron energy loss spe ctroscopy. The lattice parameters are derived as a=b=0.37 nm and c=2.69 nm with a space group of I4/mmm, which is the space group of ideal RP phase. T he advantages of high pressure sintering are discussed. (C) 2001 American I nstitute of Physics.