Crystallographic and magnetic studies of mesoporous eskolaite, Cr2O3

Mesoporous eskolaite, Cr2O3 prepared by using the evaporation method with mesoporous KIT-6 silica as a hard template has been analysed with SQUID magnetometry and variable temperature neutron powder diffraction (NPD). NPD analysis shows that the magnetic and crystallographic properties of the eskolaite structure within the walls of the mesoporous Cr2O3 material are identical to that of "bulk" material, R (3) over barc. The refined magnetic moments on the Cr3+ ions are lower than observed for bulk material due to the higher proportion of surface atoms, creating local disorder. This is corroborated by the magnetometry results, which suggest a small amount of ferromagnetism may be present at low temperatures. (C) 2009 Elsevier Inc. All rights reserved.