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American Mineralogist, Volume 95, pages 574–581, 2010 0003-004X/10/0004–574$05.00/DOI: 10.2138/am.2010.3384 574 The incommensurately modulated structures of natural natrite at 120 and 293 K from synchrotron X-ray data AllA ArAkcheevA,1 lucA Bindi,2,* PhiliP PAttison,1,3 nicolAs Meisser,4 GervAis chAPuis,1 And iGor Pekov5 1Laboratoire de Cristallographie, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland 2Museo di Storia Naturale, Sezione Mineralogia, Università di Firenze, Via La Pira 4, I-50121 Firenze, Italy 3Swiss

phlogopite-like model Þ ts the measured spectra better than a * E-mail: zanazzi@unipg.it LETTER The 10 Å phase: Crystal structure from single-crystal X-ray data P. COMODI,1 P. FUMAGALLI,2 S. NAZZARENI,1 AND P.F. ZANAZZI1,* 1Dipartimento di Scienze della Terra, Università di Perugia, Piazza Università, I-06100 Perugia, Italy 2Dipartimento di Scienze della Terra, Università di Milano, Via Botticelli 23, I-20133 Milano, Italy ABSTRACT Here we report the results of the Þ rst three-dimensional reÞ nement of the 10 Å phase performed with single-crystal X-ray data. The 10 Å

Zeitschrift für Kristallographie 212, 833-836 © by R. Oldenbourg Verlag, München 1997 833 Improved analysis of surface X-ray data G. Beneke and H. Schulz* Universität München, Institut für Kristallographie und Mineralogie, Theresienstr. 41, D-80333 München, Germany Received February 20, 1995; revised manuscript accepted in final form April 2nd, 1997 Abstract. A new method is developed for interpreting the difference Patterson function in surface X-ray structure analysis. The difference Patterson function has negative parts which arise from subtracting the

Charge Density of L-Alanyl-glycyl-L-alanine Based on X-Ray Data Collection Periods from 4 to 130 Hours Diana Förstera, Armin Wagnerb, Christian B. Hübschlea, Carsten Paulmannc, and Peter Lugera a Institut für Chemie und Biochemie/Kristallographie, Freie Universität Berlin, Fabeckstraße 36a, D-14195 Berlin, Germany b Swiss Light Source (SLS) at the Paul-Scherrer Institute, Villigen, Switzerland, and Diamond Light Source, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE, Great Britain c Mineralogisch

PART ΓΙ C A L C U L A T I O N S B A S E D ON X-RAY DATA 2.1 X-RAY PROCEDURE, SUBJECT, A N D PHONETIC MATERIAL In 1951 the subject was a 38 year old Russian, native of Moscow, and son of Moscovite intellectuals, actor of the Stanislavskiï school, who had left his country ten years before. In order to sample the phonemes of Russian, the subject was instructed to pronounce sounds in the following manner: "Say [s] as in [sat]." In the case of the continuants and the vowels, he held the primary position of the articulators until the X-ray pictures were

Different Structural Models of YB2C2 and GdB2C2 on the Basis of Single-Crystal X-Ray Data Olaf Reckeweg and Francis J. DiSalvo Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA Reprint requests to Dr. Olaf Reckeweg. Fax: ++1-607-255-4137. E-mail: olaf.reykjavik@gmx.de Z. Naturforsch. 2014, 69b, 289 – 293 / DOI: 10.5560/ZNB.2014-3333 Received December 16, 2013 Samples of YB2C2 and GdB2C2 were synthesized by arc-melting and subsequent annealing of the products. Single crystals of the title compounds were

381 A Method for the Direct Determination of Crystal Structure from X-ray Data1). By Melvin Avrami, Columbia School of Mines, New York. The method for crystal structure determination described by the author in another paper [Physic. Rev., August 15 (1938)] is studied in greater detail and an approximation method for solving the high order f u n d a m e n t a l e q u a t i o n s involved is described. I. General Equations. When a beam of X-rays is sent through crystalline matter, it is diffracted into a number of beams. These manifest themselves as

N O T I Z E N 483 Röntgenographische Daten verschiedener Amminmetalltetraoxometallate X-Ray Data of Some Amminemetaltetraoxometallates A C H I M M Ü L L E R u n d I R E N E B Ö S C H E N Institut für Chemie der Universität Dortmund (Z. Naturforech. 26 b, 483—4S4 [1971] ; eingegangen am 4. Februar 1971) Im Rahmen unserer Untersuchungen an Chalkogeno- metallaten beabsichtigen wir den Einfluß von Oxo- metallatanionen auf die inneren Schwingungen der Am- minmetallkationen zu untersuchen (entsprechend auch den Einfluß der Kationen auf die inneren Schwingun

177 Methods in Crystal Analysis. I. Fourier Series and the Interpretation of X-ray Data. By A. L . P a t t e r s o n in New York. § 1. Introduction. The technique of the determination of crystal structure from ab- solute measurements of X-ray reflection intensity has been brought to a high state of perfection by the work of W. L. Bragg 1 ) , and his collaborators. Their method determines the parameters defining the positions of the atoms constituting the crystal in question; certain as- sumptions as to the distribution of electrons in the individual

the structural sites (hereafter called site scattering) for both samples. Here we examine the problems that may be encountered during the structure refinement of olivine, another widespread group of rock-forming minerals that is intermediate between garnets and amphiboles both for symmetry and complexity. * E-mail: merli@crystal.unipv.it Determination of site population in olivine: Warnings on X-ray data treatment and refinement MARCELLO MERLI,1,2 ROBERTA OBERTI,1 FRANCA CAUCIA,1,2 AND LUCIANO UNGARETTI1,2 1CNR-Centro di Studio per la Cristallochimica e la