Determination of molecular pair correlation functions and size and shape parameters for diatomic liquids from x‐ray and neutron diffraction data

The structure determination of caesium oxalate monohydrate using single-crystal X-ray diffraction, powder neutron diffraction data and a combination of both has been undertaken. Results show that even for hydrogen-containing materials data collected rapidly on a high-flux neutron diffractometer improve the refinement such that accurate positional and thermal displacement parameters can be extracted for all atom types. This contrasts with structural models extracted from either data set alone that demonstrate the inherent limitations of the individual diffraction methods. The rapidity with which useful neutron diffraction data has been collected from hydrogen-containing compounds, 10 min in this study, indicates that the technique should be widely applicable allowing the facile and accurate extraction of hydrogen positions for many compounds.

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X-Ray and Neutron Diffraction with Amorphous Ti67Si33, V67Si33, and Cr67Si33

Zeitschrift für Naturforschung A ◽

10.1515/zna-1993-0706 ◽

1993 ◽

Vol 48 (7) ◽

pp. 777-783 ◽

Cited By ~ 1

Author(s):

A. Präffcke ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Neutron Diffraction ◽

Metallic Glasses ◽

Correlation Functions ◽

Amorphous Alloys ◽

Pair Correlation ◽

X Ray Diffraction ◽

Neutron Data ◽

Pair Correlation Functions ◽

X Ray ◽

Atomic Diameter

Abstract The amorphous alloys Ti67Si33 , V67Si33 , and Cr67Si33 were produced by sputtering. Their structure was investigated by X-ray and neutron diffraction. X-ray diffraction showed that the structure of the three metallic glasses is not isomorphous. Neutron diffraction showed that Si-Si atomic pairs occur preferentially with distances distinctly larger than the atomic diameter of the Si atoms. For T67Si33 partial pair correlation functions could be evaluated from combination of the X-ray and the neutron data.The structural results are compared with the structure of amorphous Mn74Si23P3 .

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Partial pair correlation functions of La1−x(AlGaAu)x metallic glasses from x-ray diffraction data

Solid State Communications ◽

10.1016/0038-1098(82)90318-0 ◽

1982 ◽

Vol 44 (7) ◽

pp. 983-986 ◽

Cited By ~ 5

Author(s):

Arthur Williams

Keyword(s):

Diffraction Data ◽

Metallic Glasses ◽

Correlation Functions ◽

Pair Correlation ◽

X Ray Diffraction ◽

Pair Correlation Functions ◽

X Ray

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Design of a novel Peltier-based cooling device and its use in neutron diffraction data collection of perdeuterated yeast pyrophosphatase

Journal of Applied Crystallography ◽

10.1107/s0021889810027111 ◽

2010 ◽

Vol 43 (5) ◽

pp. 1113-1120 ◽

Cited By ~ 1

Author(s):

Esko Oksanen ◽

François Dauvergne ◽

Adrian Goldman ◽

Monika Budayova-Spano

Keyword(s):

Data Collection ◽

Neutron Diffraction ◽

Diffraction Data ◽

Catalytic Mechanism ◽

Inorganic Pyrophosphatase ◽

Neutron Diffraction Data ◽

Cooling Device ◽

Data Set ◽

X Ray ◽

X Ray Crystallography

H atoms play a central role in enzymatic mechanisms, but H-atom positions cannot generally be determined by X-ray crystallography. Neutron crystallography, on the other hand, can be used to determine H-atom positions but it is experimentally very challenging. Yeast inorganic pyrophosphatase (PPase) is an essential enzyme that has been studied extensively by X-ray crystallography, yet the details of the catalytic mechanism remain incompletely understood. The temperature instability of PPase crystals has in the past prevented the collection of a neutron diffraction data set. This paper reports how the crystal growth has been optimized in temperature-controlled conditions. To stabilize the crystals during neutron data collection a Peltier cooling device that minimizes the temperature gradient along the capillary has been developed. This device allowed the collection of a full neutron diffraction data set.

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