Solid phases of spatially nanoconfined oxygen: A neutron scattering study

Enthalten in
The journal of chemical physics 
Volume
140
Issue
2
Article Number
024705
Citation
Journal of Chemical Physics 140 (2) : 024705 (2014-01-14)
Publisher DOI
10.1063/1.4860555
Scopus ID
2-s2.0-84892575227
We present a comprehensive neutron scattering study on solid oxygen spatially confined in 12 nm wide alumina nanochannels. Elastic scattering experiments reveal a structural phase sequence known from bulk oxygen. With decreasing temperature cubic γ-, orthorhombic β- and monoclinic α-phases are unambiguously identified in confinement. Weak antiferromagnetic ordering is observed in the confined monoclinic α-phase. Rocking scans reveal that oxygen nanocrystals inside the tubular channels do not form an isotropic powder. Rather, they exhibit preferred orientations depending on thermal history and the very mechanisms, which guide the structural transitions. © 2014 AIP Publishing LLC.