STRUCTURAL, TRANSPORT, AND MAGNETIC-PROPERTIES OF THE ND(1-X)A(X)TIO(3) (A=CA, SR, BA) SYSTEM WHERE 0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1

A series of perovskite Nd(1-x)A(x)TiO(3) (A = Ca, Sr, Ba) compounds ha s been prepared by the dc-arc melting technique in the composition ran ge 0 less than or equal to x less than or equal to similar to 1.0. The substitution of Sr and Ba in NdTiO3 results in structural phase trans itions from orthorhombic (Pbnm) to cubic (Pm3m). The Nd1-xCaxTiO3 seri es remains orthorhombic throughout the range studied. Low field magnet ic susceptibility measurements and remanent magnetic moment studies su ggest that the Ti sublattice in the insulating Nd(1-x)A(x)TiO(3) compo unds (0 less than or equal to x less than or equal to similar to 0.2) orders as canted antiferromagnets. The Nd(1-x)A(x)TiO(3) compounds sho w compositionally dependent metal-insulator transitions that coincide with the disappearance of the magnetic ordering. The correlations betw een the structure and transport properties are discussed in terms of t he Ti-O-Ti angle and Ti-O bond distance. The perovskite tolerance fact or, t, is also shown to be a useful parameter to sort insulating and m etallic phases in these compounds. (C) 1995 Academic Press, Inc.