X-rays diffraction on a new chromium oxide single-crystal thin film prepared by molecular beam epitaxy

Chromium oxide films were prepared on MgO substrates by molecular beam epitaxy. The crystalline structure of the films was characterized by X-ray diffraction (XRD) with conventional as well as synchrotron X-ray sources. The θ−2θ spectra showed that the film was a new chromium oxide epitaxially grown on MgO(0 0 1) substrate. The structure of the film was revealed to be body-centred orthorhombic both by reciprocal space mapping and synchrotron Q scans. The unit cell parameters were determined to be a=8.94, b=2.98 and c=3.892 Å. The film had a 45° in-plane orientation with respect to MgO substrate. The crystalline structure of the films was equivalent to a NaCl-type CrO with 13 Cr atoms vacating along MgO〈1 1 0〉 direction in an ordered way.