砷化镓200在小角中子散射中实现更高分辨率的前景。

The promise of GaAs 200 in small-angle neutron scattering for higher resolution.

作者信息

Magerl A, Lemmel H, Appel M, Weisser M, Kretzer U, Zobel M

机构信息

Biophysics Group, Physics Department Friedrich Alexander Universität Erlangen-Nürnberg Henkestrasse 91 91052Erlangen Germany.

JCNS-3: Neutron Analytics for Energy Research Forschungszentrum Jülich GmbH Wilhelm-Johnen-Strasse 52428Jülich Germany.

出版信息

J Appl Crystallogr. 2024 Aug 27;57(Pt 5):1282-1287. doi: 10.1107/S1600576724007246. eCollection 2024 Oct 1.

DOI:10.1107/S1600576724007246

PMID:39387068

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11460398/

Abstract

The resolution in Bonse-Hart double-crystal diffractometers is determined for a given Bragg angle by the value of the crystallographic structure factor. To date, the reflections Si 220 or Si 111 have been used exclusively in neutron scattering, which provide resolutions for triple-bounce crystals of about 2 × 10 Å (FWHM). The Darwin width of the GaAs 200 reflection is about a factor of 10 smaller, offering the possibility of a resolution of 2 × 10 Å provided crystals of sufficient quality are available. This article reports a feasibility study with single-bounce GaAs 200, yielding a resolution of 4.6 × 10 Å, six times superior in comparison with a Si 220 setup.

摘要

在邦斯-哈特双晶衍射仪中，对于给定的布拉格角，分辨率由晶体结构因子的值决定。迄今为止，在中子散射中仅使用了Si 220或Si 111反射，这为三反射晶体提供了约2×10 Å（半高宽）的分辨率。GaAs 200反射的达尔文宽度约小10倍，若能获得足够高质量的晶体，则有可能实现2×10 Å的分辨率。本文报道了一项使用单反射GaAs 200的可行性研究，其分辨率为4.6×10 Å，与Si 220装置相比高出六倍。