Observation of local magnetic moments in the Mott transition of ${\mathrm{V}}_2$${\mathrm{O}}_3$ by means of 3s photoemission

The 3s and 3p photoelectrons have been measured in pure and Cr-doped ${\mathrm{V}}_2$${\mathrm{O}}_3$, in the antiferromagnetic insulator, paramagnetic metal, and paramagnetic insulator phases. It is found that 3s photoemission provides us with information about local magnetic moments created by 3d electrons in these materials. They are smaller by about 15–25 % in the metal phase than those in the insulator phases. The observed results are discussed in conjunction with the Mott transition and the importance of the spin-fluctuation effect is emphasized.