An investigation of the structural dynamics in the fast ionic conductor Cu2−δSe using neutron scattering

Neutron scattering study of short-range correlations and ionic diffusion in copper selenide

“…1 originates from Se-Cu and Cu-Cu thermal correlations. The position of first two diffuse peaks agrees well with previous results [9,14]. The major contributions are from Se↔Cu (8c, 32f) and Cu (8c)↔Cu (8c) correlations.…”

“…The mixed ionic-electronic conductor Cu 2Àd Se received attention in particular due to a high ionic conductivity [1][2][3]. However until now the crystal structure and mechanism of ionic transport in Cu 2Àd Se compounds is the subject of discussion [4][5][6][7][8][9][10][11][12][13][14].…”

“…Because mobile atoms are delocalised, the Rietveld refinement of average structure suffers from strong correlations between parameters, particularly the positional parameters and vibrational/thermal displacements. At the same time disorder gives rise to broad diffuse maxima observed in neutron diffraction patterns of polycrystalline and single crystal samples of superionic conductors [9,14]. An analysis of the diffuse component provides information about the local structure, short-range correlations, which is often lost in the average structure.…”

Neutron diffraction study of diffuse scattering in Cu2−δSe superionic compounds

“…Disordered distribution of Cu atoms gives rise to broad diffuse maxima observed in neutron diffraction patterns of polycrystalline and single crystal samples of copper selenide [9,[13][14][15]. The diffuse background generally contains the elastic and inelastic scattering components originating from the static disorder and dynamic correlations, both of which affect ionic conductivity [13][14][15].…”

“…The diffuse background generally contains the elastic and inelastic scattering components originating from the static disorder and dynamic correlations, both of which affect ionic conductivity [13][14][15]. It is therefore of interest to study structural modifications along with the intensity and Q-dependence of diffuse scattering in Cu-Se compounds, as a function of temperature and composition to explore different types of disorder and short range correlations.…”