Re: Rietveld

[Le Bail Armel]

Hi,

 

Reading again the Acta Cryst. (2018). A74, 88–92 paper :

 

"So, summarized here, HS wrote in Dutch:

‘Loopstra had the idea that it should be better to use the whole powder profile 
rather than estimated intensities to solve structures, van Laar worked it out 
mathematically and Rietveld programmed it. Nowadays it is known as the Rietveld 
method’. HS submitted the raw manuscript without figures and photographs. At the 
time he was President of the IUCr, very busy and travelling a lot. So when he 
saw the article again, it was already printed, there were four illustrations 
provided by Rietveld himself, and slight changes had been made to the text, 
which in essence had changed its meaning. In the sentence above Loopstra was 
replaced by Rietveld and it now started with ‘Rietveld had the idea that...’. 
Also a last sentence about Rietveld’s hobby, as a jazz pianist, had been added."

 

This is the "coup de grace"...

 

But could Hugo Rietveld admit to be transformed in a simple programmer by  
‘Loopstra had the idea that it should be better to use the whole powder profile 
rather than estimated intensities to solve structures, van Laar worked it out 
mathematically and Rietveld programmed it' ?

 

Seriously, HS really think that Hugo Rietveld had absolutely no idea, and then 
worked out mathematically nothing ?

 

This was a complete provocation to give to Hugo Rietveld access to such an 
insulting text against him before its publication.

 

I just prefer to believe that Hugo Rietveld restored the truth by inserting 
‘Rietveld had the idea that...’. instead of Loopstra.

 

There is no proof of the contrary given by Loopstra himself, defined as a man 
"who apparently pushed hard" by Alan. He had a lot of time to push hard in 
order to contradict the legend and has done nothing apart using the method and 
citing quietly the 1969 paper from Hugo Rietveld.

 

Best,

 

Armel

 

 

 

 

 

 

> Message du 18/08/18 12:24
> De : "Alan Hewat" 
> A : le-bail.ar...@orange.fr
> Copie à : "rietveld_l@ill.fr" 
> Objet : Re: Rietveld
> 
>
> As I get older, I believe less and less in legends  (AH)
> 
> ...the aristocracy of powder diffractionists is displaced (AleB)

>
I don't believe in aristocracy either :-) After Bill David, Lambert van Eijck 
and I published Hugo Rietveld's glowing obituary, I received a rough draft of 
the vL&S paper, and was frankly shocked. But after finding that others shared 
those views, I suggested a re-write of the paper to make it (perhaps) less 
controversial and more historical, supported where possible with evidence from 
the literature. Still, the paper seemed to address questions I myself had about 
the legend.

>
1) How could a young man, educated as a classical crystallographer (Bragg 
peaks, structure factors, Fourier transforms...) produce the revolutionary idea 
of simply refining the structure to fit the observed profile ? None of the 
professional crystallographers I knew accepted that idea - only physicists and 
chemists who used crystallography as a tool. It was a naive physicist's 
approach.

>
2) How could Rietveld (1967) in his first paper not emphasise this 
revolutionary departure from classical crystallographic techniques ? It was 
almost as if he didn't consider that refining  magnetic moments and atom 
displacements was real crystallography, just a refinement problem where 
compromises had to be made to get a required result with an inadequate computer.

>
3) Why did Rietveld leave science in 1974 if he thought that he had achieved 
something remarkable ? He had a permanent job at a well funded laboratory and a 
technique that would eventually revolutionise powder diffraction. Ordinary 
people like me couldn't even get a job at Cambridge (thanks Mike :-) and had to 
live with a succession of 3 year contracts in foreign countries.

>
When I first knew Hugo, he was a modest, unassuming man, unlike Loopstra who 
apparently pushed hard. When he saw that "The response was slight, or, rather, 
non-existent" perhaps like other crystallographers for 20 years he himself 
doubted the value of profile refinement.

>
And no I don't think the crystallographic establishment should get to name it. 
Everyone knows what "profile refinement" means.


>

On Sat, 18 Aug 2018 at 11:29, Le Bail Armel  wrote:
>

> Hi,

>  

> >As I get older, I believe less and less in legends. In the IUCr 1999 issue 
> >that I cited, I should have also mentioned that there is an interesting 
> >article on p.4 called "The Powder Diffraction Handicap" by Armel le Bail :-)

>  

> Indeed, "never say never" is verified again. The powder diffraction handicap 
> (overlapping) can be considered as suppressed by XFEL

> https://www.xfel.eu/ where each single microcrystal of the powder produces 3D 
> diffraction data, and all data are recombined !

> But for solving too simple problems, you will not have access to that 
> overloaded machine and will have to continue to use your laboratory powder 
> di

Re: Rietveld

[Alan Hewat]

>  Seriously, HS really think that Hugo Rietveld had absolutely no idea,
and then worked out mathematically nothing ?

Armel, the vL&S paper
 doesn't
say that Rietveld had no idea and contributed nothing. Please read the
first line of the paper again.

*"...the method did not suddenly appear in a flash of inspiration of a
single person, but was the result of the work of three individuals...
Loopstra, van Laar and Rietveld.".*

But it's great to see you back on the Rietveld mailing list, pushing hard
for what you Believe :-)  Alan.
__
*   Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE *
 +33.476.98.41.68
http://www.NeutronOptics.com/hewat
__
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Re: Rietveld

[Le Bail Armel]

 

>"...the method did not suddenly appear in a flash of inspiration of a single 
>person, but was the result of the work of three individuals... Loopstra, van 
>Laar and Rietveld.".

 

And more precisely :

 

" HS wrote in Dutch:

‘Loopstra had the idea that it should be better to use the whole powder profile 
rather than estimated intensities to solve structures, van Laar worked it out 
mathematically and Rietveld programmed it."

 

I conclude then :

no idea for Rietveld and van Laar since they are from Loopstra;

no mathematics for Rietveld and Loopstra;

no programming for Loopstra and van Laar.

 

A very clear result of the work of three individuals. The HS view...

 

Seems that Rietveld had not the same opinion and claimed for ideas too and 
possibly for mathematics as well.

 

Best,

 

Armel

 

 

 
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Re: Rietveld

[Miguel Delgado]

Seems that Rietveld had not the same opinion and claimed for ideas too 
and possibly for mathematics as well.


Best,

Armel



Armel,

For the sake of the scientific exchange of ideas and facts, too bad that 
Dr. Rietveld is not alive.


Regards,

Miguel Delgado


On 8/19/2018 6:21 PM, Le Bail Armel wrote:


*>".../the method did not suddenly appear in a flash of inspiration of 
a single person, but was the result of the work of three 
individuals... Loopstra, van Laar and Rietveld./".*


And more precisely :

" HS wrote in Dutch:

‘Loopstra had the idea that it should be better to use the whole 
powder profile rather than estimated intensities to solve structures, 
van Laar worked it out mathematically and Rietveld programmed it."


I conclude then :

no idea for Rietveld and van Laar since they are from Loopstra;

no mathematics for Rietveld and Loopstra;

no programming for Loopstra and van Laar.

A very clear result of the work of three individuals. The HS view...

Seems that Rietveld had not the same opinion and claimed for ideas too 
and possibly for mathematics as well.


Best,

Armel



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RE: Rietveld

[Davide Levy]

Hi,

I am too young and out of the mainstream of powder diffraction to know all the 
stories about the born of the Rietveld Method. 

My question is: the article of Rietveld is published in 1969 and  the article 
about the born of this method come out after that Hugo Rietveld pass away, why 
did this happen 49 years after? 

 

Dr. Davide Levy, Ph.D.

Head of XRD laboratory
Wolfson Applied Materials Research Center
Tel Aviv University

Phone:   +972-3-6407815
Fax: +972-3-6407819
  http://www3.tau.ac.il/wamrc/ 



 

From: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] On Behalf Of 
Le Bail Armel
Sent: Monday, 20 August, 2018 2:22 AM
To: Rietveld_l@ill.fr
Subject: Re: Rietveld

 

 

>"...the method did not suddenly appear in a flash of inspiration of a single 
>person, but was the result of the work of three individuals... Loopstra, van 
>Laar and Rietveld.".

 

And more precisely :

 

" HS wrote in Dutch:

‘Loopstra had the idea that it should be better to use the whole powder profile 
rather than estimated intensities to solve structures, van Laar worked it out 
mathematically and Rietveld programmed it."

 

I conclude then :

no idea for Rietveld and van Laar since they are from Loopstra;

no mathematics for Rietveld and Loopstra;

no programming for Loopstra and van Laar.

 

A very clear result of the work of three individuals. The HS view...

 

Seems that Rietveld had not the same opinion and claimed for ideas too and 
possibly for mathematics as well.

 

Best,

 

Armel

 

 

 

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Re: Rietveld

[Alan Hewat]

*>  For the sake of the scientific exchange of ideas and facts, too bad
that Dr. Rietveld is not alive.*
Loopstra is not alive either. Scientists cannot ask anyone for the absolute
truth. We have to look at the available evidence, and different people may
reach different conclusions. If you want the opinion of the actual people
involved, you now have van Laar's account
  and you have Rietveld's
account .

*> ...why did this happen 49 years after?*
1) At Petten there was apparently a problem from the beginning. According
to vL&S 
"*After publishing this important project alone, Rietveld found his
position in the small Petten group increasingly difficult. In 1974 he
successfully applied for the post of head of the RCN library*"
2) For the first 20 years, it simply wasn't important
"*It was only really adopted by the wider crystallographic community 20
years later, after the original small group at Petten had all left science*
".
3) When the importance of the method was finally recognised, these
reservations about its origins were published, at least in the NL - D.
Andriesse (2000), H. Schenk (2001) as quoted by vL&S
.

*Just as profile refinement "did not suddenly appear in a flash of
inspiration of a single person", questions about the origin of the method
did not suddenly appear in 2018.*

On Mon, 20 Aug 2018 at 07:35, Davide Levy  wrote:

> Hi,
>
> I am too young and out of the mainstream of powder diffraction to know all
> the stories about the born of the Rietveld Method.
>
> My question is: the article of Rietveld is published in 1969 and  the
> article about the born of this method come out after that Hugo Rietveld
> pass away, why did this happen 49 years after?
>
>
>
> *Dr. Davide Levy, Ph.D.*
>
>
> *Head of XRD laboratoryWolfson Applied Materials Research Center*
> *Tel Aviv University*
>
> *Phone: +972-3-6407815 <+972%203-640-7815>*
> *Fax:   +972-3-6407819 <+972%203-640-7819>*
> *http://www3.tau.ac.il/wamrc/  *
>
> [image:
> http://www3.tau.ac.il/wamrc/templates/labs_3/images/new-tau-logo.png][image:
> WAMRC-LOGO_new]
>
>
>
> *From:* rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] *On
> Behalf Of *Le Bail Armel
> *Sent:* Monday, 20 August, 2018 2:22 AM
> *To:* Rietveld_l@ill.fr
> *Subject:* Re: Rietveld
>
>
>
>
>
> *>"...**the method did not suddenly appear in a flash of inspiration of a
> single person, but was the result of the work of three individuals...
> Loopstra, van Laar and Rietveld.**".*
>
>
>
> And more precisely :
>
>
>
> " HS wrote in Dutch:
>
> ‘Loopstra had the idea that it should be better to use the whole powder
> profile rather than estimated intensities to solve structures, van Laar
> worked it out mathematically and Rietveld programmed it."
>
>
>
> I conclude then :
>
> no idea for Rietveld and van Laar since they are from Loopstra;
>
> no mathematics for Rietveld and Loopstra;
>
> no programming for Loopstra and van Laar.
>
>
>
> A very clear result of the work of three individuals. The HS view...
>
>
>
> Seems that Rietveld had not the same opinion and claimed for ideas too and
> possibly for mathematics as well.
>
>
>
> Best,
>
>
>
> Armel
>
>
>
>
>
>
> ++
> 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/
> ++
>
>

-- 
__
*   Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE *
 +33.476.98.41.68
http://www.NeutronOptics.com/hewat
__
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