نتایج جستجو برای: neutron

تعداد نتایج: 46140  

Journal: :Acta crystallographica. Section B, Structural science 2006
Charlotte K Leech Sarah A Barnett Kenneth Shankland Matthias Gutmann Chick C Wilson

The structures of both known forms of the polymorphic material ortho-acetamidobenzamide, C(9)H(10)N(2)O(2), have been determined by low-temperature neutron single-crystal diffraction. Neutron diffraction allows the full description of the H-atom positions in this molecular material, which is vital in benchmarking related crystal-structure predictions. Significant conformational differences are ...

2010
Bjørn Clausen Donald W. Brown Carlos N. Tomé Levente Balogh Sven C. Vogel

Neutron diffraction has been used for engineering applications for nearly three decades. The basis of the technique is powder diffraction following Bragg’s Law. The measured diffraction patterns provide information about internal strains, texture and microstructure, which can be deduced from the peak positions, peak intensities, and peak widths, respectively. Most structural materials are aniso...

2013
Gerhard Fecher Hartmut Fuess

The crystal structure of the high temperature phase of anilinium bromide, CeH5NH3®Br , was studied by X-ray and neutron diffraction at T = 343 K . The refinement supports disordered positions of the —NH3® group. A split-atom model is proposed which includes disorder of the benzene ring. The thermal parameters, hydrogen bond distances, and other experimental data (NMR, N Q R , inelastic neutron ...

2011
Muhammed Yousufuddin

Neutron diffraction is the method of choice when locating chemically interesting hydrogen atoms, particularly in systems containing a heavy metal. In this article, two fascinating complexes containing hydrogen atoms that were unambiguously located with neutron diffraction will be highlighted. The first complex, OsH3Cl(PPh3)3, is a Kubas-type complex containing a rare elongated dihydrogen ligand...

2002
A. J. Burggraaf T. van Dijk M. J. Verkerk

High oxygen conductivities can be achieved in cation ordered LnxZrl_=O2_l x (Ln=Gd, Nd) solid solutions with pyrochlore (P) structure. High values of the pre-exponentlal factor °o are correlated with the degree of anion disorder in the 8b oxygen sublattice (neutron diffraction). The activation energy AH is lowered by cation ordering (F-P transition; effect of x) due to the occurence of a prefer...

2015
T. Guidi B. Gillon S. A. Mason E. Garlatti S. Carretta P. Santini A. Stunault R. Caciuffo J. van Slageren B. Klemke A. Cousson G. A. Timco R. E. P. Winpenny

Finite spin chains made of few magnetic ions are the ultimate-size structures that can be engineered to perform spin manipulations for quantum information devices. Their spin structure is expected to show finite size effects and its knowledge is of great importance both for fundamental physics and applications. Until now a direct and quantitative measurement of the spatial distribution of the m...

Journal: :Acta crystallographica. Section A, Foundations of crystallography 2007
D J Goossens T R Welberry A P Heerdegen M J Gutmann

Conventional crystallographic refinement uses the Bragg-peak intensities and gives the single-site average crystal structure. Information about short-range order and local order is contained in the diffuse scattering that is distributed throughout reciprocal space. Models of the short-range order in materials can now be automatically refined. The complementarity of X-ray and neutron diffraction...

Journal: :The journal of physical chemistry. A 2008
Wei Zhou Hui Wu Terrence J Udovic John J Rush Taner Yildirim

Using neutron inelastic scattering and diffraction, we have studied the quantum methyl rotation in zeolitic imidazolate framework-8 (ZIF-8: Zn(MeIM)(2), MeIM = 2-methylimidazolate). The rotational potential for the CH(3) groups in ZIF-8 is shown to be primarily 3-fold in character. The ground-state tunneling transitions at 1.4 K of 334 +/- 1 mueV for CH(3) groups in hydrogenated ZIF-8 (H-ZIF-8)...

Journal: :Nature materials 2014
Hoyoung Jang G Friemel J Ollivier A V Dukhnenko N Yu Shitsevalova V B Filipov B Keimer D S Inosov

Heavy-fermion metals exhibit a plethora of low-temperature ordering phenomena . Among these are the so-called hidden-order phases that, in contrast to conventional magnetic order, are invisible to standard neutron diffraction experiments. One of the structurally most simple hidden-order compounds, CeB6, has been intensively studied for an elusive phase that was attributed to the antiferroquadru...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید