EVOLUTION OF 3-DIMENSIONAL CHARACTER ACROSS THE LAN+1NINO3N+1 HOMOLOGOUS SERIES WITH INCREASE IN N

Electrical and magnetic properties of La//3Ni//2O//7 and La//4Ni//3O//1//0 have been investigated in comparison with those of La//2NiO//4, LaNiO//3, and LaSrNiO//4. The results suggest an increasing 3-dimensional character across the homologous series La//n// plus //1Ni//nO//3//n// plus //1 with increase in n. Accordingly, the electrical resistivity decreases in the order La//3Ni//2O//7, La//4Ni//3O//1//0, and LaNiO//3 and this trend is suggested to be related to the percolation threshold. Magnetic properties of these oxides also show some interesting trends across the series.