Total-energy band calculations employing a fixed-spin-moment procedure and the augmented-spherical-wave method are used to study the volume dependences and existence ranges of antiferromagnetic behavior in the 4d transition metals constrained to cubic lattices. At expanded volumes we find stable antiferromagnetic solutions of the Kohn-Sham equations for bcc niobium, molybdenum, and technetium, and for fcc technetium, and metastable antiferromagnetic solutions for fcc ruthenium. We find no stable antiferromagnetic solutions for fcc rhodium or palladium. Comparisons are made with the occurrence of antiferromagnetism in the 3d transition metals. © 1990 The American Physical Society.