@article{8f83088d95044b978c2704d63cca599c,
title = "Local structure displacements in La1−xCexOBiSSe as a function of Ce substitution",
abstract = "We have investigated the local structure of layered La1−xCexOBiSSe system by Bi L3-edge extended X-ray absorption fine structure (EXAFS) measurements for different Ce substitutions. Ce L3-edge X-ray absorption spectroscopy (XAS) has been used to evaluate the Ce valence responsible for the self-doping in this system. We have found that the local distortion, determined by the separation between two Bi-Ch distances within the BiCh2-layer (Ch=S,Se), is quickly suppressed by Ce substitution while the axial Bi-S2 bond elongates. Ce L3-edge XAS reveals a coexistence of Ce3+ and Ce4+ in which the Ce4+ weight decreases, an indication of a partial breaking of RE-S-Bi (RE=La/Ce) charge transfer channel with Ce substitution. The results suggest that interaction between REO spacer layer and BiCh2 layer, dictated by the out-of-plane Bi-S2 distance, has a significant role in triggering superconductivity in the title system, with the in-plane distortion controlling the charge mobility within the BiCh2-layer.",
keywords = "BiS2-based systems, Local structure, Self-doping, Superconductivity",
author = "Pugliese, {G. M.} and F. Stramaglia and Capone, {F. G.} and Hacisalihoglu, {M. Y.} and R. Kiyama and R. Sogabe and Y. Goto and S. Pollastri and {De Souza}, {D. Oliveira} and L. Olivi and T. Mizokawa and Y. Mizuguchi and Saini, {N. L.}",
note = "Funding Information: The authors thank Elettra staff for excellent technical support during the measurements. We would like to acknowledge JSPS support under the KAKENHI Grant Number 15H05886 and the Advanced Research Program under the Human Resources Funds of Tokyo (Grant Number: H31-1). The work is a part of the executive protocol of the general agreement for cooperation between the Sapienza University of Rome and the Tokyo Metropolitan University including the Waseda University, Japan. One of us (NLS) would like to acknowledge partial support under the joint research program of ZAIKEN, Waseda University (Project Number: 31010). Funding Information: The authors thank Elettra staff for excellent technical support during the measurements. We would like to acknowledge JSPS support under the KAKENHI Grant Number 15H05886 and the Advanced Research Program under the Human Resources Funds of Tokyo (Grant Number: H31-1 ). The work is a part of the executive protocol of the general agreement for cooperation between the Sapienza University of Rome and the Tokyo Metropolitan University including the Waseda University, Japan. One of us (NLS) would like to acknowledge partial support under the joint research program of ZAIKEN, Waseda University (Project Number: 31010 ). Publisher Copyright: {\textcopyright} 2020 Elsevier Ltd",
year = "2020",
month = dec,
doi = "10.1016/j.jpcs.2020.109648",
language = "English",
volume = "147",
journal = "Journal of Physics and Chemistry of Solids",
issn = "0022-3697",
publisher = "Elsevier Limited",
}