Premium
Origin of Pressure‐Induced Metallization in Cu 3 N: An X‐ray Absorption Spectroscopy Study
Author(s) -
Kuzmin Alexei,
Anspoks Andris,
Kalinko Aleksandr,
Timoshenko Janis,
Nataf Lucie,
Baudelet François,
Irifune Tetsuo
Publication year - 2018
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.201800073
Subject(s) - extended x ray absorption fine structure , xanes , absorption spectroscopy , x ray absorption spectroscopy , spectroscopy , lattice constant , absorption edge , crystal structure , scattering , analytical chemistry (journal) , absorption (acoustics) , copper , materials science , x ray absorption fine structure , crystallography , chemistry , band gap , diffraction , optics , metallurgy , physics , optoelectronics , chromatography , quantum mechanics , composite material
High‐pressure (0–26.7 GPa) Cu K‐edge X‐ray absorption spectroscopy is used to study possible structural modifications of anti‐perovskite‐type copper nitride (Cu 3 N) crystal lattice. The analysis of X‐ray absorption near‐edge structure (XANES) and extended X‐ray absorption fine structure (EXAFS), based on theoretical full‐multiple‐scattering and single‐scattering approaches, respectively, suggests that at all pressures the local atomic structure of Cu 3 N remains close to that in cubic P m 3 ¯ m phase. Therefore, the transition to metal state above 5 GPa, observed previously using pressure‐dependent electrical resistance and optical absorption measurements, is explained by the band gap collapse due to a decrease of the unit cell volume. We found that the lattice parameter of Cu 3 N is reduced by ≈2% upon increasing pressure up to 26.7 GPa, and the structure is restored upon pressure release.