Fermi surface of osmium

The Fermi surface for osmium is found to bear a close relationship to that for ruthenium, with corresponding areas comparable or smaller. The de Haas-van Alphen frequencies observed fall into two distinct ranges differing by a factor of about 50, the higher centered at 1.5 x 10(8) G. The energy bands calculated for rhenium with a Fermi energy appropriate for osmium suggest a Fermi surface consisting of three large sheets - a pair of nested electron-type surfaces and an open hexagonal network of hole-type arms. Our measurements clearly detect each of these surfaces. We observe additionally a single set of small ellipsoids. If these ellipsoids are hole surfaces located on faces of the Brillouin zone near U, only minor modifications of the bands calculated for rhenium are required to bring the Fermi surface into agreement with the experimental results.