The passing of Hugo Rietveld

[Alan Hewat]

*The passing of Hugo Rietveld, on the 50th anniversary of Rietveld
Refinement and the 100th anniversary of Powder Diffraction*

It is our sad duty to report the death of Hugo Rietveld at the age of 84
after a short illness. He leaves behind his wife, a son and two daughters
to whom we extend our heartfelt sympathy on behalf of the more than one
thousand members of the Rietveld Mailing List.

Hugo was born on the 7 March 1932 in The Hague and migrated to Western
Australia with his family, where in 1957 he enrolled at the University of
WA at the same time as Brian O’Connor and Syd Hall.  He obtained his Ph.D.
under the supervision of Ted Maslen who had studied under Dorothy Hodgkin
at Oxford. Hugo pioneered single crystal neutron diffraction at Lucas
Heights Sydney with Terry Sabine, and their first paper was published in
Nature in 1961.

Clews C J B, Maslen E N, Rietveld H M and Sabine T M (1961) Nature 192 154

“X-Ray and Neutron Diffraction Examination of p-Diphenylbenzene"

Hugo's experience with manual data collection and refinement convinced him
of the need to computerise such tasks, and at Lucas Heights and the UWA he
programmed two of the first IBM-1620 mainframes
 in
Fortran-II. After obtaining his Ph.D. in 1964 with Dorothy Hodgkin as
external examiner, (she had received the Nobel Prize for her work on
penicillin and vitamin B12), he joined the neutron diffraction group of the
Reactor Centrum Nederland in Petten and his interest turned to powder
diffraction because large single crystals were not available for the
inorganic materials of interest.

The young group at Petten including Bert Loopstra, Bob van Laar and Hugo
Rietveld first addressed the problem of overlapping powder reflections by
using a relatively long neutron wavelength (2.6 Å) with a pyrolytic
graphite filter. This spread out the long d-spacing peaks, allowing more of
them to be resolved, and is still a good solution for the magnetic
structures in which they were interested. However, for structure refinement
many peaks were still unresolved, and the shorter d-spacings needed for
high atomic resolution could not even be seen.

In a 1966 paper, Hugo already used intensities from overlapping Bragg
peaks. Along with others with the same problem, he then tried to fit
multiple peaks to overlapping regions, but with limited success. As well, a
neutron powder pattern took a whole week to collect, and the local
Electrologica-X1
computer  was less powerful
than the IBM-1620 - and programmed in Algol.  It was there and then that the
brilliantly simple but profound idea arose of refining the crystal
structure together with the parameters describing the peak positions and
profiles all together, as published in the famous 1969 paper.

Rietveld H M (1969) Journal of Applied Crystallography 22 65-71

“A profile refinement method for nuclear and magnetic structures”

Hugo distributed his Algol refinement program

widely, but very few papers were initially published using the method.
Discouraged by the limited funding available for neutron diffraction, he
successfully applied to become head of the library department at Petten.

One of us (AH), who had also completed his Ph.D. at Lucas Heights in 1970
and who had moved to Harwell, encountered the same problems with neutron
diffraction for structural transitions. On the advice of George Bacon, AH
visited Hugo in 1971 and brought back Hugo's new Fortran-II version of the
profile refinement program. A Harwell version
,
modified to model the anisotropic vibrations preceding structural
transitions, was very successful, both at Harwell and with Brian Fender's
students at Oxford, in particular Tony Cheetham and Bob von Dreele.

In 1973, when the UK joined the EEC and AH moved to ILL in Grenoble,
another Oxford student (WIFD) performed his first neutron powder
experiments on AH's new D1A high resolution diffractometer, where a powder
pattern took only one day to collect, and later only one hour. Again this
work was very successful, and the number of papers using what Terry Sabine,
in 1978, christened the "Rietveld Method" exploded, supported by new
computer programs including those of the early Oxford-Grenoble champions
Bob von Dreele and Juan Rodriguez-Carvajal. Yet it was not until 1977 that
R.A. Young and colleagues applied the method to X-ray powder diffraction,
leading to further rapid growth in the number of publications. Thousands of
X-ray publications using Rietveld Refinement are now published every year.

Perhaps the 

Re: The passing of Hugo Rietveld

[Fabrizio Guzzetta]

May he rest in peace. He did a great job for all the crystallographers.

Fabrizio Guzzetta
Ph.D. student, Dept. Quimica Inorganica y Organica, UJI
Castellon de la Plana
Spain

2016-07-19 14:57 GMT+02:00 Alan Hewat :

> *The passing of Hugo Rietveld, on the 50th anniversary of Rietveld
> Refinement and the 100th anniversary of Powder Diffraction*
>
> It is our sad duty to report the death of Hugo Rietveld at the age of 84
> after a short illness. He leaves behind his wife, a son and two daughters
> to whom we extend our heartfelt sympathy on behalf of the more than one
> thousand members of the Rietveld Mailing List.
>
> Hugo was born on the 7 March 1932 in The Hague and migrated to Western
> Australia with his family, where in 1957 he enrolled at the University of
> WA at the same time as Brian O’Connor and Syd Hall.  He obtained his Ph.D.
> under the supervision of Ted Maslen who had studied under Dorothy Hodgkin
> at Oxford. Hugo pioneered single crystal neutron diffraction at Lucas
> Heights Sydney with Terry Sabine, and their first paper was published in
> Nature in 1961.
>
> Clews C J B, Maslen E N, Rietveld H M and Sabine T M (1961) Nature 192 154
> 
> “X-Ray and Neutron Diffraction Examination of p-Diphenylbenzene"
>
> Hugo's experience with manual data collection and refinement convinced him
> of the need to computerise such tasks, and at Lucas Heights and the UWA he
> programmed two of the first IBM-1620 mainframes
>  
> in
> Fortran-II. After obtaining his Ph.D. in 1964 with Dorothy Hodgkin as
> external examiner, (she had received the Nobel Prize for her work on
> penicillin and vitamin B12), he joined the neutron diffraction group of the
> Reactor Centrum Nederland in Petten and his interest turned to powder
> diffraction because large single crystals were not available for the
> inorganic materials of interest.
>
> The young group at Petten including Bert Loopstra, Bob van Laar and Hugo
> Rietveld first addressed the problem of overlapping powder reflections by
> using a relatively long neutron wavelength (2.6 Å) with a pyrolytic
> graphite filter. This spread out the long d-spacing peaks, allowing more of
> them to be resolved, and is still a good solution for the magnetic
> structures in which they were interested. However, for structure refinement
> many peaks were still unresolved, and the shorter d-spacings needed for
> high atomic resolution could not even be seen.
>
> In a 1966 paper, Hugo already used intensities from overlapping Bragg
> peaks. Along with others with the same problem, he then tried to fit
> multiple peaks to overlapping regions, but with limited success. As well, a
> neutron powder pattern took a whole week to collect, and the local 
> Electrologica-X1
> computer  was less
> powerful than the IBM-1620 - and programmed in Algol.  It was there and
> then that the brilliantly simple but profound idea arose of refining the
> crystal structure together with the parameters describing the peak
> positions and profiles all together, as published in the famous 1969 paper.
>
> Rietveld H M (1969) Journal of Applied Crystallography 22 65-71
> 
> “A profile refinement method for nuclear and magnetic structures”
>
> Hugo distributed his Algol refinement program
> 
> widely, but very few papers were initially published using the method.
> Discouraged by the limited funding available for neutron diffraction, he
> successfully applied to become head of the library department at Petten.
>
> One of us (AH), who had also completed his Ph.D. at Lucas Heights in 1970
> and who had moved to Harwell, encountered the same problems with neutron
> diffraction for structural transitions. On the advice of George Bacon, AH
> visited Hugo in 1971 and brought back Hugo's new Fortran-II version of the
> profile refinement program. A Harwell version
> ,
> modified to model the anisotropic vibrations preceding structural
> transitions, was very successful, both at Harwell and with Brian Fender's
> students at Oxford, in particular Tony Cheetham and Bob von Dreele.
>
> In 1973, when the UK joined the EEC and AH moved to ILL in Grenoble,
> another Oxford student (WIFD) performed his first neutron powder
> experiments on AH's new D1A high resolution diffractometer, where a powder
> pattern took only one day to collect, and later only one hour. Again this
> work was very successful, and the number of papers using what Terry Sabine,
> in 1978, christened the "Rietveld Method" exploded, supported by 

Re: grazing incidence, step in XRD pattern

[Martin Vickers]

It's possible it's in your other patterns, too, but because you don't have
much background in those, you'll have to look very closely to see anything.
I agree it's likely to be a detector issue.

Regards,

Martin

On 4 July 2016 at 10:14, Thomas Winter 
wrote:

> Hey Jeff,
>
> Thank you very much for your quick response. If the detector is the issue,
> how come the “step” is only visible while measuring Fe, Co and Mn?
>
> I am still going to try out your suggestion! Am happy for every idea I can
> get! J
>
> Kind regards,
>
> Thomas Winter
>
>
-- 
Martin Vickers
Dept. of Chemistry, UCL,
20, Gordon Street
WC1H 0AJ
020 7679 5592 (or ex 25592)
++
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: The passing of Hugo Rietveld

[Aga Shahee]

>
> I am deeply touched by the death of *Professor** Rietveld*. I present my
> sincere condolences to his family, his friends and all those who knew
> him. His contribution to field of crystallography will be remembered
> for ever.
>
>
>-
>
>-
>
>With warm regards
>
> Aga Shahee
>
> Post-Doc Fellow
>
> Dept. of Physics
>
> IITB, Mumbai, India
>
> Email Id: sha...@phy.iitb.ac.in
>   -
>
>  Contact No: +91-9892712175
>   -
>
>  Lab. Ext.: 4567/4697
>   -
>
>
>   -
>
>
>
>
> On Tue, Jul 19, 2016 at 7:38 AM, Reese, Bill L <
> bill.l.re...@exxonmobil.com> wrote:
>
>> Very sad to hear this news.  Dr. Rietveld changed the course of my
>> career.  I regret not getting the chance to meet him.
>>
>>
>>
>>
>>
>>
>>
>> *William L. (Bill) Reese*
>>
>>
>>
>> *X-ray Diffraction Laboratory*
>>
>>
>>
>> *Rietveld Analysis*
>>
>> *Mineral Quantification*
>>
>> *Clay Mineralogy*
>>
>>
>>
>> (832)624-9030
>>
>>
>>
>> Lab Building
>>
>> LB 3B 320
>>
>> 22777 Springwoods Village PKWY
>>
>> Spring, TX  77389
>>
>>
>>
>> *bill.l.re...@exxonmobil.com *
>>
>>
>>
>> *From:* rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] *On
>> Behalf Of *Alan Hewat
>> *Sent:* Tuesday, July 19, 2016 7:58 AM
>> *To:* rietveld_l@ill.fr
>> *Subject:* The passing of Hugo Rietveld
>>
>>
>>
>> *The passing of Hugo Rietveld, on the 50th anniversary of Rietveld
>> Refinement and the 100th anniversary of Powder Diffraction*
>>
>>
>>
>> It is our sad duty to report the death of Hugo Rietveld at the age of 84
>> after a short illness. He leaves behind his wife, a son and two daughters
>> to whom we extend our heartfelt sympathy on behalf of the more than one
>> thousand members of the Rietveld Mailing List.
>>
>>
>>
>> Hugo was born on the 7 March 1932 in The Hague and migrated to Western
>> Australia with his family, where in 1957 he enrolled at the University of
>> WA at the same time as Brian O’Connor and Syd Hall.  He obtained his Ph.D.
>> under the supervision of Ted Maslen who had studied under Dorothy Hodgkin
>> at Oxford. Hugo pioneered single crystal neutron diffraction at Lucas
>> Heights Sydney with Terry Sabine, and their first paper was published in
>> Nature in 1961.
>>
>>
>>
>> Clews C J B, Maslen E N, Rietveld H M and Sabine T M (1961) Nature 192 154
>> 
>>
>> “X-Ray and Neutron Diffraction Examination of p-Diphenylbenzene"
>>
>>
>>
>> Hugo's experience with manual data collection and refinement convinced
>> him of the need to computerise such tasks, and at Lucas Heights and the UWA
>> he programmed two of the first IBM-1620 mainframes
>>  
>> in
>> Fortran-II. After obtaining his Ph.D. in 1964 with Dorothy Hodgkin as
>> external examiner, (she had received the Nobel Prize for her work on
>> penicillin and vitamin B12), he joined the neutron diffraction group of the
>> Reactor Centrum Nederland in Petten and his interest turned to powder
>> diffraction because large single crystals were not available for the
>> inorganic materials of interest.
>>
>>
>>
>> The young group at Petten including Bert Loopstra, Bob van Laar and Hugo
>> Rietveld first addressed the problem of overlapping powder reflections by
>> using a relatively long neutron wavelength (2.6 Å) with a pyrolytic
>> graphite filter. This spread out the long d-spacing peaks, allowing more of
>> them to be resolved, and is still a good solution for the magnetic
>> structures in which they were interested. However, for structure refinement
>> many peaks were still unresolved, and the shorter d-spacings needed for
>> high atomic resolution could not even be seen.
>>
>>
>>
>> In a 1966 paper, Hugo already used intensities from overlapping Bragg
>> peaks. Along with others with the same problem, he then tried to fit
>> multiple peaks to overlapping regions, but with limited success. As well, a
>> neutron powder pattern took a whole week to collect, and the local 
>> Electrologica-X1
>> computer  was less
>> powerful than the IBM-1620 - and programmed in Algol.  It was there and
>> then that the brilliantly simple but profound idea arose of refining the
>> crystal structure together with the parameters describing the peak
>> positions and profiles all together, as published in the famous 1969 paper.
>>
>>
>>
>> Rietveld H M (1969) Journal of Applied Crystallography 22 65-71
>> 
>>
>> “A profile refinement method for nuclear and magnetic structures”
>>
>>
>>
>> Hugo distributed his Algol refinement program
>> 
>> widely, but very few papers were initially published using the method.
>> Discouraged by the limited funding available for neutron 

Re: The passing of Hugo Rietveld

[Sudhindra Rayaprol]

Kindly pass on our heartfelt condolences to the family of Prof. Rietveld. May 
his kind soul rest in peace. He shall be remembered by all of us for his 
immense contribution in popularizing powder diffraction as a unique and 
powerful tool in material characterization. 

RIP

Sudhindra Rayaprol


On 07/19/16 06:35 PM, Alan Hewat   wrote: 
> 
> 
> 
> The passing of Hugo Rietveld, on the 50th anniversary of Rietveld Refinement 
> and the 100th anniversary of Powder Diffraction
> 
> 
>  
> It is our sad duty to report the death of Hugo Rietveld at the age of 84 
> after a short illness. He leaves behind his wife, a son and two daughters to 
> whom we extend our heartfelt sympathy on behalf of the more than one thousand 
> members of the Rietveld Mailing List.
>  
> Hugo was born on the 7 March 1932 in The Hague and migrated to Western 
> Australia with his family, where in 1957 he enrolled at the University of WA 
> at the same time as Brian O’Connor and Syd Hall. He obtained his Ph.D. under 
> the supervision of Ted Maslen who had studied under Dorothy Hodgkin at 
> Oxford. Hugo pioneered single crystal neutron diffraction at Lucas Heights 
> Sydney with Terry Sabine, and their first paper was published in Nature in 
> 1961. 
>  
> Clews C J B, Maslen E N, Rietveld H M and Sabine T M (1961) Nature 192 
> 154(http://www.nature.com/nature/journal/v192/n4798/abs/192154a0.html)
> “X-Ray and Neutron Diffraction Examination of p-Diphenylbenzene"
>  
>  
> Hugo's experience with manual data collection and refinement convinced him of 
> the need to computerise such tasks, and at Lucas Heights and the UWA he 
> programmed two of the first IBM-1620 
> mainframes(http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP1620.html)
>  in Fortran-II. After obtaining his Ph.D. in 1964 with Dorothy Hodgkin as 
> external examiner, (she had received the Nobel Prize for her work on 
> penicillin and vitamin B12), he joined the neutron diffraction group of the 
> Reactor Centrum Nederland in Petten and his interest turned to powder 
> diffraction because large single crystals were not available for the 
> inorganic materials of interest. 
> 
> 
> 
>  
> The young group at Petten including Bert  Loopstra,  Bob van Laar  and Hugo 
> Rietveld first addressed the problem of overlapping powder reflections by 
> using a relatively long neutron wavelength (2.6 Å) with a pyrolytic graphite 
> filter. This spread out the long d-spacing peaks, allowing more of them to be 
> resolved, and is still a good solution for the magnetic structures in which 
> they were interested. However, for structure refinement many peaks were still 
> unresolved, and the shorter d-spacings needed for high atomic resolution 
> could not even be seen. 
> 
> 
> 
> 
> In a 1966 paper, Hugo already used intensities from overlapping Bragg peaks. 
> Along with others with the same problem, he then tried to fit multiple peaks 
> to overlapping regions, but with limited success. As well, a neutron powder 
> pattern took a whole week to collect, and the local Electrologica-X1 
> computer(https://ub.fnwi.uva.nl/computermuseum//X1.php) was less powerful 
> than the IBM-1620 - and programmed in Algol.   It was there and then that the 
> brilliantly simple but profound idea  arose of refining the crystal structure 
> together with the parameters describing the peak positions and profiles all 
> together, as published in the famous 1969 paper. 
> 
>  
> Rietveld H M (1969) Journal of Applied Crystallography 22 
> 65-71(http://scripts.iucr.org/cgi-bin/paper?a07067) 
>  
> “A profile refinement method for nuclear and magnetic structures”
> 
>  
> 
> Hugo distributed his Algol refinement 
> program(http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/46/087/46087996.pdf)
>  widely, but very few papers were initially published using the method. 
> Discouraged by the limited funding available for neutron diffraction, he 
> successfully applied to become head of the library department at Petten.
> 
>  
> 
> One of us (AH), who had also completed his Ph.D. at Lucas Heights in 1970 and 
> who had moved to Harwell, encountered the same problems with neutron 
> diffraction for structural transitions. On the advice of George Bacon, AH 
> visited Hugo in 1971 and brought back Hugo's new Fortran-II version of the 
> profile refinement program. A Harwell 
> version(http://hewat.net/science/papers/1973_The_Rietveld_Program_for_the_Profile_Refinement_of_%20Neutron_Diffraction_Powder_Patterns_AERE_R7350-von_Dreele_annotations.pdf),
>  modified to model the anisotropic vibrations preceding structural 
> transitions, was very successful, both at Harwell and with Brian Fender's 
> students at Oxford, in particular Tony Cheetham and Bob von Dreele. 
> 
> 
> 
> In 1973, when the UK joined the EEC and AH moved to ILL in Grenoble, another 
> Oxford student (WIFD) performed his first neutron powder experiments on AH's 
> new D1A high resolution 

Re: The passing of Hugo Rietveld

[S. D. Kaushik]

it is really a huge loss for the community for powder diffraction. Prof.
Rietveld's work was path breaking, which altogether changed the way of
looking the thing in crystallography.
May the God give the strength to the family and near and dear to overcome
this great loss and may the soul rest in peace..

kaushik

On Wed, Jul 20, 2016 at 2:39 AM,  wrote:

>
> A sad day indeed for powder diffraction. The impact of Hugo Rietveld's
> work can never be overestimated. Developing and applying the Rietveld
> method has been central to my work for >30 years.
>
> Cheers
>
>
>
> ooo0ooo
>
>  Ian Madsen
>  Honorary Fellow
>  CSIRO Mineral Resources Flagship
>  Private Bag 10,  Clayton South 3169
>  Victoria,   AUSTRALIA
>  Phone +61 3 9545 8785 direct
>  +61 3 9545 8500 switch
>  +61 (0) 417 554 935 mobile
>  FAX+61 3 9562 8919
>  Email ian.mad...@csiro.au
>
> ooo0ooo
> --
> *From:* rietveld_l-requ...@ill.fr  on behalf
> of Alan Hewat 
> *Sent:* Tuesday, July 19, 2016 10:57:44 PM
> *To:* rietveld_l@ill.fr
> *Subject:* The passing of Hugo Rietveld
>
> *The passing of Hugo Rietveld, on the 50th anniversary of Rietveld
> Refinement and the 100th anniversary of Powder Diffraction*
>
> It is our sad duty to report the death of Hugo Rietveld at the age of 84
> after a short illness. He leaves behind his wife, a son and two daughters
> to whom we extend our heartfelt sympathy on behalf of the more than one
> thousand members of the Rietveld Mailing List.
>
> Hugo was born on the 7 March 1932 in The Hague and migrated to Western
> Australia with his family, where in 1957 he enrolled at the University of
> WA at the same time as Brian O’Connor and Syd Hall.  He obtained his Ph.D.
> under the supervision of Ted Maslen who had studied under Dorothy Hodgkin
> at Oxford. Hugo pioneered single crystal neutron diffraction at Lucas
> Heights Sydney with Terry Sabine, and their first paper was published in
> Nature in 1961.
>
> Clews C J B, Maslen E N, Rietveld H M and Sabine T M (1961) Nature 192 154
> 
> “X-Ray and Neutron Diffraction Examination of p-Diphenylbenzene"
>
> Hugo's experience with manual data collection and refinement convinced him
> of the need to computerise such tasks, and at Lucas Heights and the UWA he
> programmed two of the first IBM-1620 mainframes
>  
> in
> Fortran-II. After obtaining his Ph.D. in 1964 with Dorothy Hodgkin as
> external examiner, (she had received the Nobel Prize for her work on
> penicillin and vitamin B12), he joined the neutron diffraction group of the
> Reactor Centrum Nederland in Petten and his interest turned to powder
> diffraction because large single crystals were not available for the
> inorganic materials of interest.
>
> The young group at Petten including Bert Loopstra, Bob van Laar and Hugo
> Rietveld first addressed the problem of overlapping powder reflections by
> using a relatively long neutron wavelength (2.6 Å) with a pyrolytic
> graphite filter. This spread out the long d-spacing peaks, allowing more of
> them to be resolved, and is still a good solution for the magnetic
> structures in which they were interested. However, for structure refinement
> many peaks were still unresolved, and the shorter d-spacings needed for
> high atomic resolution could not even be seen.
>
> In a 1966 paper, Hugo already used intensities from overlapping Bragg
> peaks. Along with others with the same problem, he then tried to fit
> multiple peaks to overlapping regions, but with limited success. As well, a
> neutron powder pattern took a whole week to collect, and the local 
> Electrologica-X1
> computer  was less
> powerful than the IBM-1620 - and programmed in Algol.  It was there and
> then that the brilliantly simple but profound idea arose of refining the
> crystal structure together with the parameters describing the peak
> positions and profiles all together, as published in the famous 1969 paper.
>
> Rietveld H M (1969) Journal of Applied Crystallography 22 65-71
> 
> “A profile refinement method for nuclear and magnetic structures”
>
> Hugo distributed his Algol refinement program
> 
> widely, but very few papers were initially published using the method.
> Discouraged by the limited funding available for neutron diffraction, he
> successfully applied to become head of the library department at Petten.
>
> One of us (AH), who had also completed his Ph.D. at Lucas Heights in 1970
> and 

Re: The passing of Hugo Rietveld

[Ian.Madsen]

A sad day indeed for powder diffraction. The impact of Hugo Rietveld's work can 
never be overestimated. Developing and applying the Rietveld method has been 
central to my work for >30 years.

Cheers



ooo0ooo

 Ian Madsen
 Honorary Fellow
 CSIRO Mineral Resources Flagship
 Private Bag 10,  Clayton South 3169
 Victoria,   AUSTRALIA
 Phone +61 3 9545 8785 direct
 +61 3 9545 8500 switch
 +61 (0) 417 554 935 mobile
 FAX+61 3 9562 8919
 Email ian.mad...@csiro.au

ooo0ooo

From: rietveld_l-requ...@ill.fr  on behalf of Alan 
Hewat 
Sent: Tuesday, July 19, 2016 10:57:44 PM
To: rietveld_l@ill.fr
Subject: The passing of Hugo Rietveld

The passing of Hugo Rietveld, on the 50th anniversary of Rietveld Refinement 
and the 100th anniversary of Powder Diffraction

It is our sad duty to report the death of Hugo Rietveld at the age of 84 after 
a short illness. He leaves behind his wife, a son and two daughters to whom we 
extend our heartfelt sympathy on behalf of the more than one thousand members 
of the Rietveld Mailing List.

Hugo was born on the 7 March 1932 in The Hague and migrated to Western 
Australia with his family, where in 1957 he enrolled at the University of WA at 
the same time as Brian O’Connor and Syd Hall.  He obtained his Ph.D. under the 
supervision of Ted Maslen who had studied under Dorothy Hodgkin at Oxford. Hugo 
pioneered single crystal neutron diffraction at Lucas Heights Sydney with Terry 
Sabine, and their first paper was published in Nature in 1961.

Clews C J B, Maslen E N, Rietveld H M and Sabine T M (1961) Nature 192 
154
“X-Ray and Neutron Diffraction Examination of p-Diphenylbenzene"

Hugo's experience with manual data collection and refinement convinced him of 
the need to computerise such tasks, and at Lucas Heights and the UWA he 
programmed two of the first IBM-1620 
mainframes
 in Fortran-II. After obtaining his Ph.D. in 1964 with Dorothy Hodgkin as 
external examiner, (she had received the Nobel Prize for her work on penicillin 
and vitamin B12), he joined the neutron diffraction group of the Reactor 
Centrum Nederland in Petten and his interest turned to powder diffraction 
because large single crystals were not available for the inorganic materials of 
interest.

The young group at Petten including Bert Loopstra, Bob van Laar and Hugo 
Rietveld first addressed the problem of overlapping powder reflections by using 
a relatively long neutron wavelength (2.6 Å) with a pyrolytic graphite filter. 
This spread out the long d-spacing peaks, allowing more of them to be resolved, 
and is still a good solution for the magnetic structures in which they were 
interested. However, for structure refinement many peaks were still unresolved, 
and the shorter d-spacings needed for high atomic resolution could not even be 
seen.

In a 1966 paper, Hugo already used intensities from overlapping Bragg peaks. 
Along with others with the same problem, he then tried to fit multiple peaks to 
overlapping regions, but with limited success. As well, a neutron powder 
pattern took a whole week to collect, and the local Electrologica-X1 
computer was less powerful than 
the IBM-1620 - and programmed in Algol.  It was there and then that the 
brilliantly simple but profound idea arose of refining the crystal structure 
together with the parameters describing the peak positions and profiles all 
together, as published in the famous 1969 paper.

Rietveld H M (1969) Journal of Applied Crystallography 22 
65-71
“A profile refinement method for nuclear and magnetic structures”

Hugo distributed his Algol refinement 
program
 widely, but very few papers were initially published using the method. 
Discouraged by the limited funding available for neutron diffraction, he 
successfully applied to become head of the library department at Petten.

One of us (AH), who had also completed his Ph.D. at Lucas Heights in 1970 and 
who had moved to Harwell, encountered the same problems with neutron 
diffraction for structural transitions. On the advice of George Bacon, AH 
visited Hugo in 1971 and brought back Hugo's new Fortran-II version of the 
profile refinement program. A Harwell 
version,
 modified to model the anisotropic vibrations preceding structural transitions, 
was