Local disorder investigation in NiS2-xSex using Raman and Ni K-edge x-ray absorption spectroscopies


Autoria(s): Marini, C; Joseph, B; Caramazza, S; Capitani, F; Bendele, M; Mitrano, M; Chermisi, D; Mangialardo, S; Pal, B; Goyal, M; Iadecola, A; Mathon, O; Pascarelli, S; Sarma, DD; Postorino, P
Data(s)

2014

Resumo

We report on Raman and Ni K-edge x-ray absorption investigations of a NiS2-xSex (with x = 0.00, 0.50/0.55, 0.60, and 1.20) pyrite family. The Ni K-edge absorption edge shows a systematic shift going from an insulating phase (x = 0.00 and 0.50) to a metallic phase (x = 0.60 and 1.20). The near-edge absorption features show a clear evolution with Se doping. The extended x-ray absorption fine structure data reveal the evolution of the local structure with Se doping which mainly governs the local disorder. We also describe the decomposition of the NiS2-xSex Raman spectra and investigate the weights of various phonon modes using Gaussian and Lorentzian profiles. The effectiveness of the fitting models in describing the data is evaluated by means of Bayes factor estimation. The Raman analysis clearly demonstrates the disorder effects due to Se alloying in describing the phonon spectra of NiS2-xSex pyrites.

Formato

application/pdf

Identificador

http://eprints.iisc.ernet.in/50356/1/jou_phy_con_mat_26-45_2014.pdf

Marini, C and Joseph, B and Caramazza, S and Capitani, F and Bendele, M and Mitrano, M and Chermisi, D and Mangialardo, S and Pal, B and Goyal, M and Iadecola, A and Mathon, O and Pascarelli, S and Sarma, DD and Postorino, P (2014) Local disorder investigation in NiS2-xSex using Raman and Ni K-edge x-ray absorption spectroscopies. In: JOURNAL OF PHYSICS-CONDENSED MATTER, 26 (45).

Publicador

IOP PUBLISHING LTD

Relação

http://dx.doi.org/ 10.1088/0953-8984/26/45/452201

http://eprints.iisc.ernet.in/50356/

Palavras-Chave #Solid State & Structural Chemistry Unit
Tipo

Journal Article

PeerReviewed