In:
Journal of Applied Crystallography, International Union of Crystallography (IUCr), Vol. 47, No. 1 ( 2014-02-01), p. 60-66
Abstract:
The formation and growth of nanosized CaF 2 crystallites by heat treatment of an oxyfluoride glass of composition 7.65Na 2 O–7.69K 2 O–10.58CaO–12.5CaF 2 –5.77Al 2 O 3 –55.8SiO 2 (wt%) was investigated using anomalous small-angle X-ray scattering (ASAXS). A recently developed vacuum version of the hybrid pixel detector Pilatus 1M was used for the ASAXS measurements below the Ca K -edge of 4038 eV down to 3800 eV. ASAXS investigation allows the determination of structural parameters such as size and size distribution of nanoparticles and characterizes the spatial distribution of the resonant element, Ca. The method reveals quantitatively that the growing CaF 2 crystallites are surrounded by a shell of lower electron density. This depletion shell of growing thickness hinders and finally limits the growth of CaF 2 crystallites. Moreover, in samples that were annealed for 10 h and more, additional very small heterogeneities (1.6 nm diameter) were found.
Type of Medium:
Online Resource
ISSN:
1600-5767
DOI:
10.1107/S1600576713030100
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
2014
detail.hit.zdb_id:
2020879-0
