X-Ray magnetic circular dichroism on vanadium molecular derivatives

X-Ray Magnetic Circular Dichroism experiments have been conducted on a vanadium inorganic salt and a vanadium enamino-ketone complex. Measurements at the K edge of oxygen and nitrogen reveal the amount of magnetic moment transferred in the 2p orbitals of the ligand atoms from the magnetic V ion. Measurements at the L edge of vanadium show that the orbital moment is small and that J=L+S, contrary to the expected coupling for a 3d metal with less than five d-electrons. This surprising inobservance of Hund's third rule emphasizes the need for more detailed studies and calculations on such hybrid molecules.