title: Atomic disorder of Li0.5Ni0.5O thin films caused by Li doping: estimation from X-ray Debye-Waller factors.
abstract: Cubic type room-temperature (RT) epitaxial Li0.5Ni0.5O and NiO thin films with [111] orientation grown on ultra-smooth sapphire (0001) substrates were examined using synchrotron-based thin-film X-ray diffraction. The 1[Formula: see text]1 and 2[Formula: see text]2 rocking curves including six respective equivalent reflections of the Li0.5Ni0.5O and NiO thin films were recorded. The RTB1factor, which appears in the Debye-Waller factor, of a cubic Li0.5Ni0.5O thin film was estimated to be 1.8 (4) Å2from its 1[Formula: see text]1 and 2[Formula: see text]2 reflections, even though the Debye model was originally derived on the basis of one cubic element. The corresponding Debye temperature is 281 (39) K. Furthermore, theB2factor in the pseudo-Debye-Waller factor is proposed. This parameter, which is evaluated using one reflection, was also determined for the Li0.5Ni0.5O thin film by treating Li0.5Ni0.5O and NiO as ideal NaCl crystal structures. A structural parameter for the atomic disorder is introduced and evaluated. This parameter includes the combined effects of thermal vibration, interstitial atoms and defects caused by Li doping using the two Debye-Waller factors.
authors.affiliation: Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS),1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.
authors.forename: Anli
authors.initials: A
authors.lastname: Yang
authors.affiliation: Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS),1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan ; Synchrotron X-ray Group, Quantum Beam Unit, NIMS, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan ; Department of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259-J3-16 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan ; Global Research Center for Environment and Energy Based Nanomaterials Science, Lithium Air Battery Specially Promoted Research Team, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Osami
authors.initials: O
authors.lastname: Sakata
authors.affiliation: Department of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259-J3-16 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Yamauchi
authors.affiliation: Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS),1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.
authors.forename: L S R
authors.initials: LS
authors.lastname: Kumara
authors.affiliation: Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS),1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan ; Global Research Center for Environment and Energy Based Nanomaterials Science, Lithium Air Battery Specially Promoted Research Team, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Chulho
authors.initials: C
authors.lastname: Song
authors.affiliation: Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS),1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Katsuya
authors.affiliation: Department of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259-J3-16 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan.
authors.forename: Akifumi
authors.initials: A
authors.lastname: Matsuda
authors.affiliation: Department of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259-J3-16 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Yoshimoto
keywords: Debye–Waller factors; Li doping; atomic disorder; thin films