Mat. Res. Bull., Vol. 17, pp. 1429-1435, 1982. Printed in the USA. 0025-5408/82/111429-07503.00/9 Copyright (c) 1982 Pergamon Press Ltd. MAGNETIC PROPERTIES OF METALLIC La2 CuO~ R. Saez Puche Departamento de Qu~mica Inorg~nica, Facultnd de Ciencias Qu~micas, Universidad Complutense, Madrid - 3, Spain M. Norton and W. S. Glaunslnger Department of Chemistry, Arizona State University, Tempe, Arizona 85287 (Received September 28, 1982; Communicated by A. W. Sleight) ABSTRACT X-ray, magnetic susceptibility, and electron paramagnetic resonance measurements have been made on La2CuO4. Magnetic measurements in the range 4.2 - 300 K are consistent with the metallic nature of La2CuO., and the itinerant - electron susceptibility is estimated to be ~39 x 10-6 emu mol -I. The high susceptibility and density of states indicate that the conduction band is narrow. The results are discussed in terms of previous models of the level structure of La2CuO4, and it is concluded that conduction occurs via a o~2 -2 band. Comparison of La2CuO~ with semiconductlng lant~ide cuprates suggests that this compound is on the verge of a semlconductor-to-metal transition. Introduction Compounds having the general formula ~B~ usually adopt the tetragonal ~NIF~ structure if the A and B cation radii are in the range 1.0 < rA < 1.9 A-and 0.5 < rB < 1.2 A, respectively, and X = 0, F, and C1 (Fig. I). In this structure thelarger A cation is coordinated to nine X llgands, whereas the smaller B cation exhibits octahedral coordination. The ~B~ structure can be visualized as containing alternating perovsklte (ABe) and rock-salt (AX) blocks, with the A cation adopting a coordination number which is the average between the perovskite and rock-salt structures. The interest in 1429