Force Constants of Cu Crystals from Diffuse Neutron Scattering Measurement

T. Sakuma (Institute of Applied Beam Science, Ibaraki University, Mito 310-8512, Japan)
S.R. Mohapatra (Institute of Applied Beam Science, Ibaraki University, Mito 310-8512, Japan)
H. Uehara (Institute of Applied Beam Science, Ibaraki University, Mito 310-8512, Japan)
R. Sakai (Institute of Applied Beam Science, Ibaraki University, Mito 310-8512, Japan)
Xianglian Xianglian (College of Physics and Electronics Information, Inner Mongolia University for the Nationalities, Tongliao 028043, China)
H. Takahashi (Institute of Applied Beam Science, Ibaraki University, Hitachi 316-8511, Japan)
N. Igawa (Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai 319-1195, Japan)
K. Basar (Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung 40132, Indonesia)

Atom Indonesia Journal
Vol 36, No 3 (2010): December 2010

Diffuse neutron scattering measurement on Cu crystals was performed at 10 K and 300 K. Oscillatory forms were observed in the diffuse scattering intensities. The observed diffuse scattering intensities are analyzed by including the correlation effects among thermal displacements of atoms in the theory. Using the values of correlation effects among neighboring atoms and the values of Debye-Waller temperature parameter, force constants among first, second and third nearest neighboring atoms have been evaluated. The result of correlation effects in Cu crystals are compared to that of ionic crystal and semiconductor. The relation between correlation effects and the inter-atomic distance is not depending much on the crystal binding types. Received: 12 October 2010; Revised: 22 October 2010; Accepted: 16 December 2010