AW: Hyper-Lorentzian effect on quantitative analysis
> But with some electronic transmission analysis no amorphous is observed. Could the TEM investigation have led to recrystallisation? Have you tried polarised-light microscopy to check the character of the amorphous phase? Cheers, Uwe -Ursprüngliche Nachricht- Von: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] Im Auftrag von Wörle Michael Gesendet: Mittwoch, 03. März 2021 15:32 An: rietveld_l@ill.fr Betreff: AW: Hyper-Lorentzian effect on quantitative analysis Dear François, Maybe you have a strongly disordered system. Depending on the type of disorder and the distribution of diffuse intensity, it can also have an influence on the reflection profile (thermal diffuse scattering). Michael Dr. Michael Wörle Head Small Molecule Crystallography Center Laboratorium für Anorganische Chemie ETH Zürich HCI H103 Vladimir-Prelog-Weg 1 CH-8093 Zürich Tel.: +41 44 632 5684 FAX: +41 44 632 1149 email: woe...@inorg.chem.ethz.ch http://www.smocc.ethz.ch --- The Zurich School of Crystallography, University of Zurich, June 6-17, 2021 http://www.chem.uzh.ch/linden/zsc --- -Ursprüngliche Nachricht- Von: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] Im Auftrag von François Goutenoire Gesendet: Wednesday, 3 March 2021 13:34 An: rietveld_l@ill.fr Betreff: Hyper-Lorentzian effect on quantitative analysis Dear Rietveld users, I have some industrial compound presenting a strong hyper-Lorentzian peak shape (eta=1.1 with HighScore). When we calculate the amorphous content after an internal standard addition, the result is 40%. The micro-absorption effect has been minimized (mu of the internal standard is closed to the compound). But with some electronic transmission analysis no amorphous is observed. The question is : Does a strong hyper-Lorentzian peak shape could influence quantitative analysis ? François -- * Pr. Francois GOUTENOIRE e-mail: francois.gouteno...@univ-lemans.fr Tel: 02.43.83.33.54 FAX: 02.43.83.35.06 Skype Entreprise visio conférence Département des Oxydes et Fluorures Institut des Molécules et des Matériaux du Mans IMMM - UMR CNRS 6283 Université du Maine - Avenue Olivier Messiaen F-72085 Le Mans Cedex 9 FRANCE * Formation Rietveld CNRS 2020 https://cnrsformation.cnrs.fr/diffraction-des-rayons-x-sur-materiaux-polycristallins?axe=135 Formation EDX CNRS 2020 https://cnrsformation.cnrs.fr/fluorescence-x-edx?axe=135 Formation SAXS et Réflectivités pour couches minces et matériaux nanostructurés. https://cnrsformation.cnrs.fr/caracterisation-des-materiaux-nanostructures-par-diffusion-des-rayons-x?axe=135 Bibliographie https://scholar.google.fr/citations?hl=fr&user=qC-lmN4J&view_op=list_works&authuser=1&sortby=title https://orcid.org/-0001-5339-3002 ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++
AW: Stoichiometry and occupancy fractions of solid solutions
Dear Othman, You should check if the synthesised grains in your powder are chemically homogeneous of if they show any zonation due to growth processes. Variable chemistry will cause broadened and/or asymmetric peaks Are vacancies known to occur in this class of compounds? The conditions of preparation might be important (synthesis in air or something else?). Uwe Von: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] Im Auftrag von Othman Al Bahri Gesendet: Montag, 19. Dezember 2016 09:54 An: rietveld_l@ill.fr Betreff: Stoichiometry and occupancy fractions of solid solutions Dear all, I've made a series of solid solution powders using a solid state reaction in the form A2B3-xCxO12 at x= 0.5 steps. A2B3O12 is orthorhombic while A2C3O12 is monoclinic. I'm refining the XRD data to find the atomic distribution of the solute. I've constrained the sum of the occupancy fractions for each relevant site to equal 1. At low concentrations of the solute, I initially set the solute's occupancy fractions to 0 and keep the solvent's occupancy at 1 then refine the fractions (after following the usual Rietveld refinement steps). This seems to give reasonable occupancy fraction values (no big numbers or negative values) but the stoichiometry is way off. This is probably because each site has different Wykoff multiplicities so constraining the sum of each site's fractions to 1 is insufficient. Let's assume that I knew the stoichiometry from Mass Spectroscopy or XPS - is there a way to constrain the stiochiometry in a Rietveld refinement? I'm using GSAS-II and comfortable with FullProf but feel free to give advice for any other open-source software. I've seen a few papers where the authors mention, typically in the supplementary info, that their refinements' stoichiometry was off and that it should be ignored. However I'm not comfortable with this approach and would appreciate your advice. This is my first time working with solid solutions so please feel free to offer any general advice on what I should be careful with. I've tested for phase mixtures (insolubility) by visually comparing my XRD patterns with the sum of simulated XRD patterns of molar mixtures and through Rietveld refinements with two phases. The system I'm working with has been reported but the original authors didn't do Rietveld refinements - they were interested in physical property measurements. Kind Regards, Othman ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++
Re: peak position of W L-alpha for Cu X-ray tube
http://xray.uu.se/hypertext/XREmission.html > can you remind me what the peak position of the tungsten L-alpha for the Cu > X-ray tube? * Univ.-Doz. Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum, Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] website: http://www.univie.ac.at/mineralogie/kolitsch.htm **
Re: Bazhenovite
Dear Armel, obviously the structure of bazhenovite is unknown (although bright orange to yellow, tabular xls up to 5 mm were reported). The mineral is said to be the monoclinic analog of the synthetic rhombic compound CaS5.CaS2O3.6Ca(OH)2.20H2O (Lutz, H. D. et al, 1969). I don't know about the stability - maybe it's discussed in the original publication. I could give you the contact address of a Russian colleague who should know more about this mineral (contact me off-list then). Regards, Uwe > Hello, > > Any opinion of the eminent mineralogists members > of this mailing list welcome about bazhenovite (ICDD-JCPDS > card No 42-1361 and 22-0154) Ca8S5(S2O3)(OH)12.(H2O)20 > > Is the structure determined ? > If not, are the cell and space group dubious or not ? > Anyway, is the compound stable in air ? > > Thanks a lot, > > Armel Le Bail > http://www.cristal.org/course/ > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Minerals with unknown structure (>300)
Dear Armel, it's a very good idea to put such a list on the web. If it is regularly updated it would also help to spread structural information faster than the ICSD (which is always lagging behind a considerable time), and would help to avoid double work. Please feel free to incorporate the information below. Structures of the following minerals are already solved: benauite (not on your list; our lab, to be published, CCD single-crystal data) cafetite (Krivovichev, pers. comm., to be published; CCD data) hydrocerussite (Pluth et al., pers. comm., to be published; powder and single-crystal data) duhamelite (our lab; member of descloizite group, CCD data, to be published) elyite (not on your list; Am. Mineral. 85 (2001), 1816-1821; CCD data). kingite (not on your list; Pring, pers. comm., to be published, powder data) lavendulan (our lab, to be published, CCD data) Marthozite (not on your list; Cooper, pers. comm., Can. Mineral. (in press); CCD data) namibite (Am. Mineral. 85 (2000), 1298-1301; CCD data) priceite (Pring, pers. comm., to be published, powder data) pushcharovskite (Eur. J. Mineral. 12 (2000), 95-104; single-crystal data) rankachite (not on your list; our lab, to be published, CCD single-crystal data) rimkorolgite (?) (I remember some paper on this one) satterlyite (not on your list; our lab,Eur. J. Mineral. (in press); CCD data) shcherbakovite (Krivovichev, pers. comm., to be published; CCD data) trimounsite (not on your list; our lab, to be published, CCD data) tuperssuatsiaite (Garvie, pers. comm., in press; CCD data) uranopilite (Brugger, pers. comm., to be published) wycheproofite (not on your list; our lab, to be published, CCD data) Other minerals on the list are known to belong to a group of isostructural minerals; thus, their structures obviously only need to be refined. Cheers, Uwe >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Site occupation factor in atoms
No, there is no way, unfortunately (referring to V. 5.0). This also means that you have to be careful when you calculate a powder pattern with ATOMS - it doesn't take into account mixed occupancies, vacancies, etc.. (You may be able to trick the program a bit by choosing an element with an 'equivalent' no. of electrons.) Uwe > > Dear All, > > is there any way of defining the "site occupation factor" of an atom in > the software "ATOMS"?? > > Gracias!! > > ana > > -- > Ana Isabel Becerro > ICMSE (CSIC) > Avda. Américo Vespucio s/n > 41092 Sevilla (Spain) > Tel: 34-95 4489576 > Fax: 34 95 4460665 > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Information in Atom Program
Dear Irini, do you mean the program ATOMS by Eric Dowty? Defining polyhedra in ATOMS is pretty straight forward by using Input1/Polyhedra (I am referring to version 5.0). Defining the no. of atoms or the size of the structure fragment drawn is done in Input1/Boundary. If you want to draw different polyhedra for identical cations then it would be easiest to just change the type of atoms. The inbuilt manual will help you in any other questions. Uwe >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: cubic lithium niobium oxide
Flux growth and crystal structure determination of trilithium niobate Shishido et al. (1996) J. Alloys Compounds 234, 256-259 Li3NbO4 Ukei et al. (1994) Acta Cryst. C50, 655-656. Synthesis and structures of the partially ordered rock salt phases, Li3M2XO6: M = Mg, Co, Ni; X = Nb, Ta, Sb. Mather et al. (1995) Mater. Chem. 5, 1177-1182 Cheers, Uwe >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: LaAlO3 structure
E. Taspinar and A.C. Tas (1997): Low-Temperature Chemical Synthesis of Lanthanum Monoaluminate. J. Am. Ceram. Soc., 80 [1], 133-141. (contains results of Rietveld refinement of rhombohedral LaAlO3) H. Lehnert, H. Boysen, J. Schneider, F. Frey, D. Hohlwein, P. Radaelli, H. Ehrenberg (2000): A powder diffraction study of the phase transition in LaAlO3. Zeitschrift für Kristallographie, 2000, 215, 536-541. H. Lehnert, H. Boysen, P. Dreier, Y. Yu (2000): Room temperature structure of LaAlO3. Zeitschrift für Kristallographie, 215, 145-xx. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Database stories
In the latest edition of the ICSD there is actually the entry of khademite you found (Bachet et al., 1981). The ICSD collection code is 41-562. Cheers, Uwe >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Natrite - Na2 CO3
0.0230 0. (1) (5) (3)(10) Na 30.0050 0.0148 0.0157 0. 0.0030 0. (1) (4) (3) (1) C 10.0025 0.0073 0.0059 0. 0.0010 0. (1) (6) (4) (2) O 10.0031 0.0190 0.0115 0. 0.0035 0. (1) (6) (3) (2) O 20.0058 0.0093 0.0135 0.0014 0.0020 -0.0008 (2) (7) (3) (4) (2) (4) REM MOD (modulated/incommensurate structure) REM M PDF 37-451 RVAL 0.108 TEST Calculated density unusual but tolerable. (Code 23) >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Structure of Gorgeyite
-X- -Y- -Z- -SOF- Ca 1 2.0008f 0.14857(4) 0.48314(4) 0.42274(10) Ca 2 2.0008f 0.28210(4) 0.20681(4) 0.37465(10) Ca 3 2.0004e 1/2 1/4 0.08789(14) K 1 1.0008f 0.06662(5) 0.08944(6) 0.10865(13) S 1 6.0008f 0.36792(5) 0.08811(5) 0.41503(11) S 2 6.0008f 0.42453(5) 0.38308(4) 0.09998(11) S 3 6.0008f 0.21580(4) 0.34618(4) 0.38849(11) O 1 -2.0008f 0.10118(11) 0.42389(11) 0.1067(3) O 2 -2.0008f 0.13631(10) 0.34132(11) 0.4722(3) O 3 -2.0008f 0.41207(10) 0.17381(10) 0.3614(3) O 4 -2.0008f 0.38070(11) 0.03539(11) 0.2693(3) O 5 -2.0008f 0.27828(10) 0.07444(11) 0.4247(3) O 6 -2.0008f 0.20250(11) 0.28060(11) 0.2256(3) O 7 -2.0008f 0.26207(11) 0.42879(10) 0.3288(3) O 8 -2.0008f 0.39780(11) 0.31376(11) 0.2344(3) O 9 -2.0008f 0.14414(10) 0.12189(11) 0.4669(3) O 10 -2.0008f 0.23774(11) 0.17762(11) 0.0397(3) O 11 -2.0008f 0.44686(11) 0.45739(11) 0.2109(3) O 12 -2.0008f 0.00564(11) 0.11918(11) 0.4841(3) OH2 13 -2.0004e 0. 1/4 0.2308(5) H 1 1.0008f 8 Atoms not located in Unit Cell WYCK f18 e2 ITF Ca 1 B=0.57(2) ITF Ca 2 B=0.59(2) ITF Ca 3 B=0.63(2) ITF K 1 B=1.70(2) ITF S 1 B=0.54(2) ITF S 2 B=0.52(2) ITF S 3 B=0.50(2) ITF O 1 B=1.13(2) ITF O 2 B=1.07(2) ITF O 3 B=1.10(2) ITF O 4 B=1.05(2) ITF O 5 B=0.94(2) ITF O 6 B=1.14(2) ITF O 7 B=0.99(2) ITF O 8 B=1.12(2) ITF O 9 B=1.01(2) ITF O 10 B=0.99(2) ITF O 11 B=1.24(2) ITF O 12 B=1.00(2) ITF O 13 B=2.48(2) REM H Anisotropic temperature factors used in the refinment but not given in the paper REM M PDF 19-997 REM M entry = 20778 RVAL 0.026 TEST Calculated density unusual but tolerable. (Code 23) >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Re: Calcium iron titanium oxide
Dear Bruce, the following is from the ICSD database (only one entry for the compound): COL ICSD Collection Code 203100 DATE Recorded Dec 27, 1990 NAME Tricalcium titanium diiron(III) oxide FORM Ca3 Ti Fe2 O8 = Ca3 Fe2 O8 Ti TITL Perovskite Threefold Superlattices: A Structure Determination of the A3 M3 O8 Phase REF Materials Research Bulletin MRBUA 24 (1989) 423-430 AUT Rodriguez Carvajal J, Vallet RegiÿM, Gonzalez CalbetÿJÿM CELL a=5.530(0) b=11.205(1) c=5.438(0) à=90.0 á=90.0 ç=90.0 V=336.9 Z=2 SGR P c m 21 (26) - orthorhombic CLAS mm2 (Hermann-Mauguin) - C2v (Schoenflies) PRS oP28 ANX A3B3X8 PARM Atom__No OxStat Wyck -X- -Y- -Z- -SOF- Fe 1 3.0002a 0.309(2)0. 0.050(2) Ti 1 4.0004c 0.258(1)0.3303(5) 0.0.5 Fe 2 3.0004c 0.258(1)0.3303(5) 0.0.5 Ca 1 2.0002b 0.234(2)1/2 0.486(4) Ca 2 2.0004c 0.225(1)0.1884(5) 0.526(3) O 1 -2.0002a 0.398(6)0. 0.410(6) O 2 -2.0002b 0.316(5)1/2-0.010(7) O 3 -2.0004c 0.169(3)0.144(2) -0.018(5) O 4 -2.0004c -0.010(5)0.353(2)0.227(7) O 5 -2.0004c 0.469(5)0.300(2)0.281(6) WYCK c5 b2 a2 ITF Fe 1 B=0.57(4) ITF Ti 1 B=0.57(4) ITF Fe 2 B=0.57(4) ITF Ca 1 B=0.57(4) ITF Ca 2 B=0.57(4) ITF O 1 B=0.57(4) ITF O 2 B=0.57(4) ITF O 3 B=0.57(4) ITF O 4 B=0.57(4) ITF O 5 B=0.57(4) REM XDP (X-ray diffraction from a powder) RVAL 0.128 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Dr. Uwe Kolitsch Institut für Mineralogie und Kristallographie Geozentrum Universität Wien Althanstr. 14 A-1090 Wien Austria Tel +43-1-4277-53239 Fax +43-1-4277-9532 e-mail: [EMAIL PROTECTED] home page: http://www.univie.ac.at/mineralogie/kolitsch.htm >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
