IR Spectra of La1.85Sr0.15Cu1−xMxO4−δ(M = Zn, Ni, Mg)

Structure refinement for La1.85Sr0.15Cu1 − xNixO4 (x = 0–0.19) transition‐metal oxides

“…The lattice parameters of undoped La 1.85 Sr 0.15 CuO 4 sample are a = 3.77709(8) Å, c = 13.2368(4) Å, the axial ratio c / a is 3.5045(2). These lattice parameter values match well those previously reported in literature, obtained with either X‐ray or neutron diffraction methods (the best agreement is with datasets ##2, 3, 6 and 7, see Table ). An overview of the diffraction patterns collected for all x values indicates that there is no phase transition with increasing Ni concentration level in the whole investigated range.…”

“…Therefore the range of low‐Ni‐concentration is worth of detailed studies. The previously reported structural data of Ni‐doped LSCO represent mostly lattice parameters evolution differed by absolute values at a few x values only and not all trends were clear because of scatter of experimental points. The aim of present study was to extend the existing knowledge by determination of fine structural details of this material and their variation with nickel content at the Cu site.…”

“…The axial ratio c / a decreases by ~0.2% from 3.5045(2) Å to 3.4595(3) Å. These observations are qualitatively consistent with the results of Refs . but show a considerably smaller scatter of the experimental points, revealing that the studied dependences are smooth.…”

“…show, this result gives a clearer image of the distance variation than a few experimental points of Ref . which only indicate the observed tendency and information obtained in Ref . by IR transmittance spectra confirming directions of Cu―O bond changes.…”

“…Refined lattice parameters, axial ratio and volume, versus Ni atomic fraction at Cu site (■), (solid lines as a results of fitting are also given). Literature data are represented by experimental points: open circles,open triangles, stars and dotted lines showing the trends observed in Ref …”