Hello,
I'm new to the group and just want to say "hi". I look forward to learning
more of the secrets and intricacies of Rietveld. I'm a TOPAS user so
anything geared to that topic will be especially interesting.
Cheers,
Bill
William L. Reese
Co. Mail: URC-URC-N267
ExxonMobil Upstream Research
Hi Everyone,
I am a PhD student at the Camborne School of Mines (University of
Exeter) in the UK, carrying out a project on Rietveld refinement of
kaolinites. I've just started using our SGI Workstation and various MSI
(Molecular Simulations) software packages for Rietveld analyses. It
looks lik
Dear list-members,
As a new member let me introduce myself. My name is Michael
Ploetze.
I am a postdoc at ETH Zurich since 1998
(http://www.igt.ethz.ch/).
Past experiences: PhD at the Freiberg University of mining and
technology (Germany) (http://www.mineral.tu-freiberg.de).
My current resear
Dear All,
As a new member of the list let me introduce myself.
My name is Leonid Solovyov. I am a researcher at the
Institute of Chemistry and Chemical Technology
of the Russian Academy of Sciences.
Current activities:
Determination and refinement of the crystal structures
of inorganic and m
Hi There
My name is Caroline Kirk and I am about to start a Post Doc at the
Department of Engineering Materials, University of Sheffield.
My main scientific interests, stemming from my Ph.D. research,
involve solving complex inorganic structures from powder diffraction
data, using a combinati
Hello all,
I am Ph.D.student at the Indian Institute of Science, Bangalore. I am a
beginner in Rietveld Analysis.
-Nagesh S.Kini
Hello ,all
I'm a PhD student in Xiamen University,P.R.China.
Our group is carrying out research in the electrode materials of lithium ion batteries.
I'm a new user of Rietveld refinement,expecting your helps.
Best wishes,
Hansan Liu
Dear all
I'm new to the newsgroup and would like to introduce myself.
I'm a PhD student at Goteborg University in Gothenburg, Sweden. I work at
the Solid State Chemistry group. Rietveld method is an interest of mine due
to the studies on strontium doped lanthanum manganites we've done with
ne
Hi!
Just thought i'd quickly introduce myself as I am a new member.
Currently a postdoc researcher in layered oxide materials.
Donna
Dear users of the Rietveld mailing list,
My name is Alexander Schmets and currently I work as a PhD student in the
Neutron scattering department at the Delft University of Technology, The
Netherlands. I read this Rietveld already quite some time, but this is my
first question.
1) I have a range o
Dear users of the Rietveld mailing list,
My name is Alexander Schmets and currently I work as a PhD student in the
Neutron scattering department at the Delft University of Technology, The
Netherlands. I read this Rietveld already quite some time, but this is my
first question.
1) I have a range o
Alexander:
Your problem is quite similar to one I had to solve in my thesis where I
had a number of mixed valence sites. I also had at my disposal X-ray and
neutron data. The method that I will now mention may be manipulated to
help.
I found the need to match expected stoichiometric results (know
Alexander:
I just finished combined X+N refinement of similar battery materials but w/o
V with Li in 2a site and Mn, Co and Ni in 2b (or vise versa).
Chemical composition was well known; The problem we were looking for was
migration/exchange of transition metal from 2b to 2a.
That's not so simple p
Since we're on the subject of battery materials, we published some work
recently where we didn't assume that it was the Ni that went to the Li site in
LiMn1/3Ni1/3Co1/3O2. It's logical if it's Ni2+ but we had the data to test it
in the form of resonant scattering data to add some more informat
We didn't assume that Ni goes to the Li sites it was the only choice
confirmed by others, and it is not so simple as the full occupancy and
stoichiometry should be measured accurately. BTW sample composition as well
as sample preparation is a very crucial factor where and what goes.
I believe that
Peter
I dont know your chemical system but my first thought is that assuming
full occupancy may be too much of an sssumption. In the system I looked
at vacancies of up to 7% were observed. In fact the vacancy limit
probably determines the stability of a phase and when the limit is
reached there's
That's right. The assumption was made just to simplify discussion; in
reality of course there were no assumptions. By the way in that particular
case it is possible to refine more that 1 occupancy (Ni/Li), e.g. total
metal content.
Peter
Peter Y. Zavalij
Director, X-ray Crystallographic Laborato
Peter
It sounds like you were able to refine on the occupancies without
physically unreasonable site occupancies. I am also sure that you have
simplified the discussion for clarity. This is fine but I would add as a
hint to Alexander that making a number of series of samples can assist
greatly in
That's right, doing series of samples brings great confidence that
everything was done right (of course if there is agreement the series),
especially when you are approaching border line of the possible, which may
be the case here since 4-5% of transition metal is only 1 electron.
Peter Y. Zavalij
>Are there any other researchers who use all three techniques
>together? I'd be interested in hearing your experiences.
Quite a lot using both XRD and ND, may be less adding
SAED simultaneously.
Determining a structure (indexing, extracting structure factors,
solving...) is better (IMHO) discus
rgot to send in my introduction.)
I have a question here:
When selecting new powder diffractometer, if there any special consideration (
type of detector, optics, monochromator etc.) for an SPDP(Structural
Determination from Powder Data) machine than a rietveld machine?
Say if you are doing riet
At 10:38 AM 5/4/2005, Alexander J.M. Schmets wrote:
Consider I know (from other experiments) that V5+ (partly) occupies a 16d
site ...should I attribute instead of V the element that is five places
backwards (Argon) to that site, in order to have the correct scattered
intensity? And then ... the bo
I perfectly agree that many times lattice parameters and bond lengths
are to be given more confidence than occupation factors. It's the
canonical way to distinguish Al and Si in aluminosilicates (e.g. micas)
and we applied it successfully also to determine Li-Co exchange in
LixCoO2 battery mate
Dear all,
I am a fresh Ph.D student and I wish to learn about XRD analysis and
rietveld analysis. Can anyone help me in this regard. Please suggest
me the books I have to follow for rietveld analysis.
smith
> I am a fresh Ph.D student and I wish to learn about XRD analysis and
> rietveld analysis. Can anyone help me in this regard. Please suggest
> me the books I have to follow for rietveld analysis.
The following book is a good start - and includes example data on a CD-ROM:
Fundamentals of Powder
Lachlan,
You refer to hard cover edition of the book (ISBN: 1-4020-7365-8) but soft
cover (ISBN: 0-387-24147-7) is priced at much lower price and is available
at www.springeronline.com and amazon.com.
Regards,
Peter
Peter Y. Zavalij
Director, X-ray Crystallographic Laboratory
Department of Chem
Hi,
as a new subscriber to the Rietveld mailing list I would like to
introduce
myself. My name is Holger Kohlmann and I am a postdoc in the group of
Prof. Yvon, Institute of Crystallography, University of Geneva,
Switzerland. My research is about the determination of metal hydride
crystal struct
Dear all,
I am a new member of this mailing list. My background is environmental
engineer. At the moment I am conducting a research related to the
crystalline iron oxide magnetite. One of the analyses that I have to do is
the determination the unit cell dimension (lattice parameter) of the crystal
Hiya all.
A joint introduction and question. I'm a PDF with Canada's National
Research Council working on cathode materials for lithium ion batteries (yes
we do use neutrons!). My background is in oxides of various types and I
have an interest in time resolved diffraction studies.
-
,' \
| (
\__Montevideo, Uruguay
From: Gumelar Pritosiwi [mailto:pritos...@gmail.com]
Sent: Thursday, May 14, 2009 8:30 AM
To: rietveld_l@ill.fr
Subject: Introduction and Unit cell parameter determination
Dear all,
I am a new member of this mailing list. My background is environmental
eng
Leopoldo Suescun
>
> Prof. Agr (Assoc. Prof.) de Física Tel: (+598 2) 9290648/9249859
>
> Cryssmat-Lab./DETEMA Fax: (+598 2) 9241906
>
> Facultad de Quimica, Universidad de la Republica
>
> ,_.
>
> | \
>
> | v-
>
> ,' \
>
> |
__
De : Leopoldo Suescun
À : Gumelar Pritosiwi ; rietveld_l@ill.fr
Envoyé le : Jeudi, 14 Mai 2009, 15h45mn 16s
Objet : RE: Introduction and Unit cell parameter determination
Dear Gumelar Pritosiwi,
There are two independent topics in your question. If you are using a well
calibrated convent
Hi,
I'm playing with Fullprof again for the first time in many years since I've
changed employer and lost my access to Topas.
Is it possible to introduce independent peaks (i.e. peaks whose positions are
not determined by a unit cell) with refinable positions, intensities and shapes
in Fullpro
In a message dated 6/17/99 4:27:13 PM Pacific Daylight Time,
[EMAIL PROTECTED] writes:
<< I'm a PDF with Canada's National
Research Council >>
What's a PDF with Canada's National Research Council?
PDF: Post Doctoral (research) Fellow
Canada's Research Council= CNRS in France
A. Mulaba
From: [EMAIL PROTECTED]
Date: Fri, 18 Jun 1999 01:21:35 EDT
Subject: Re: Introduction and GSAS chemical constraints question
To:[EMAIL PROTECTED]
Rep
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Date:18 Jun 99 16:07
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Subject: Re: Introduction and GSAS chemical constraints question
Was read at 15:11, 18 Jun 99.
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Subject: Re: Introduction and GSAS chemical constraints question
Was read at 16:16, 18 Jun 99.
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Subject: Re: Introduction and GSAS chemical constraints question
Was read at 18:00, 18 Jun 99.
Dr. Josef Breu
Institut fuer Anorganische
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Was read at 18:39, 18 Jun 99.
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Was read at 15:39, 18 Jun 99.
Jens Wenzel Andreasen"If only those geologists would let me
Dept. of Miner
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Date:18 Jun 99 16:07
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Subject: Re: Introduction and GSAS chemical constraints question
Was read at 9:05, 21 Jun 99.
***
[EMAIL PROTECTED]
Chemistry Dept.,
University of Newcastle
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Was read at 9:48, 21 Jun 99.
+
Dr
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-
Michel Nieuwoudt
Senior Research Officer
Raman and
its known value and refine zero error or sample
> displacement parameter (use Full profile fit prerentially as indicated by
> Leopoldo).
>
> Patrick
>
> --
> *De :* Leopoldo Suescun
> *À :* Gumelar Pritosiwi ; rietveld_l@ill.fr
> *Envoyé le :*
IMHO, it's not a good idea to introduce independent peaks with refinable
positions, intensities, shapes and other parameters, simply to reduce your
R-factor or save time. You risk reducing the confidence you can have in
your structural parameters.
That is why Rietveld defined the background rather
Dear Magnus,
Here is a way to fit independent peaks in FullProf :
1. edit .pcr file and add for every independent peak an artificial phase
to treat in Profile Matching refinement mode (Jbt=2 and Irf=0). You can
use P m m m space group for example and adjust the a parameter to fit
with
regards,
Magnus
From: rietveld_l-requ...@ill.fr On Behalf Of Alan W
Hewat
Sent: 25 April 2022 15:50
To: rietveld_l@ill.fr
Subject: Re: Introduction of non-structural peaks in Fullprof
Dear Thierry and Magnus.
Introducing an extra pseudo-phase, and then editing out all the peaks you don't
OK Magnus, I see your point. But making a background file is not very work
intensive, even for lots of samples. It's just clicking on points on a
computer plot, and if its diffuse/disorder scattering the background will
only vary slowly. If you only have a couple of extra peaks, you can also
exclud
:*rietveld_l-requ...@ill.fr *On
Behalf Of *Alan W Hewat
*Sent:* 25 April 2022 15:50
*To:* rietveld_l@ill.fr
*Subject:* Re: Introduction of non-structural peaks in Fullprof
Dear Thierry and Magnus.
Introducing an extra pseudo-phase, and then editing out all the peaks
you don't want, is inge
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