what can freely available powder diffraction software via the internet do for you? l. m. d....

$: What can freely available powder diffraction software via the Internet do for you? L. M. D. Cranswick, CCP14 (Collaborative Computation Project No 14 for$
What can freely available powder diffraction software via the Internet do for you?

L. M. D. Cranswick, CCP14 (Collaborative Computation Project No 14 for

Single Crystal and Powder Diffraction)

Department of Crystallography;

Birkbeck College, University of London,

Malet Street, Bloomsbury, London, WC1E 7HX, UK.

E-mail: [email protected]

WWW: http://www.ccp14.ac.uk

Lachlan M. D. Cranswick ([email protected]) http://www.ccp14.ac.ukSlide 2

Notes Free Zone - they are on the web

http://www.ccp14.ac.uk/poster-talks/wpd_2002/

• Some areas of this talk may resemble a rather fast computer slide show; thus detailed notes are on the web for examination at your leisure (and given out during the talk)


Talk Aims• Show there is a variety of freely

available software out there that can help you with your research via diffraction and crystallographic methods

• Making use of the latest software can make your difficult problems easier or doable.

• Most software described can be freely usable by anyone


For those new to Crystallography

• Why bother looking into freely available crystallographic software?

• Crystallography can help answer questions that may not seem very crystallographic at the time.

• In the following screen images, help determine, using diffraction techniques, whether there is Oxygen in the Earth’s outer core.(unit cell volumes to obtain equations of state - EOS)

“O2 volumes at high pressure from KClO4 decomposition: D" as a siderophile element pump instead of a lid on the core.” D. Walker, S.M. Clark, L.M.D. Cranswick, M.C. Johnson and R.L. Jones, (2002), Geochemistry, Geophysics, Geosystems (G^3), in press.


Using the right crystallographic method can make the difference!Using Le Bail fitting / RietveldUsing Traditional UNIT CELL refinement Methods


The risks of “not knowing what you don’t know”

Thus this talk will try and get the keywords out that you can follow-up on at your leisure.


Why bother knowing about a variety of modern software? (1 of 2)

Path of Most Resistance?

Using a variety of “state-of-the-art” tools can improve versatility by allowing different pathways and approaches to tackle crystallographic problems.

– Maximise the ability to handle present and future problems

– Be able to cross hurdles that may be intractable or unnecessarily problematic if not approached the right way.


Why bother knowing about freely available software? (2 of 2)

Much freely available software is state of the art in both algorithms and usability - (GUIs)

• Concentrate on the crystallography

• Can be installed on as many computers as you want - where-ever you like

• Can take programs home and use on their personal computers (negate software piracy problems)


Talk Agenda•Start from Data conversion and phase identification

•Go through to photo realistically rendering crystal structures•Via stops including

– Peak profiling

– Unit Cell refinement

– Powder indexing

– Structure Solution

– Structure refinement

– Structure validation

– Photorealistic rendering of crystal structures


Powder Data Conversion / Importing Data

Initial problem in powder diffraction can be getting the data in the right format. For interconverting powder diffraction data: a variety of programs exist which in combination can pretty much get you from one format to another

Summary list of available software: http://www.ccp14.ac.uk/solution/powderdataconv/

Text Editors may occassionally be required: converting UNIX ACSII to DOS ASCII, getting rid of spaces or tabs , column editing:

Freeware PFE Editor for Windows:

http://www.lancs.ac.uk/people/cpaap/pfe/Freeware ConTEXT Editor for Windows (does column editing)

http://www.fixedsys.com/context/

Example of ConvX for Windows by Mark BowdenMass data powder diffraction data converter


Phase Identification/Search Match for Powder Diffraction

•Two main parts to perform computer based search-match:– 1. Have a Powder Diffraction Database (buy or make your own)

– 2. Search-match software that uses the above database to search

•Databases:– ICDD has the commercial powder diffraction database area cornered

http://www.icdd.com

– Alternative being developed is the Pauling File: http://www.pauling.com• Editor in Chief: Dr Pierre Villars

•Nearly all Search-match programs are commercial:

•Refer to, "Available Search-Match Software" for a list of known software:– http://www.ccp14.ac.uk/solution/search-match.htm

– Free Software:Brian Toby's "Portable Logic Program" (UNIX) and "MacDiff" for Apple Mac freeware by Rainer Petschick

– Look out for the developing OpenXRD by Stefan Krumm (UNIX and Windows)


Phase Identification/Search Match for Powder Diffraction 2 of 3Identifying an organic – DL-Valine

33- 1954 DL-VALINE

File Name: c:\...\valine.cpi

Valine

2-Theta Angle (deg)10.00 20.00 30.00 40.00 50.00

1

Inte

nsity

(C

ount

s) X

100

000


Which software, databases and methods work the best: Search Match Round Robin (2nd May 2002 to 30th June 2002):

http://sdpd.univ-lemans.fr/smrr/ and CCP14 mirrors

•Conclusions :

– Accurate search-match without chemistry is possible but:

– Need up to date database

– Need good 3rd generation search-match software

– Need a skilled analyst

– (the skilled analyst seems to be the most important of the 3)


Has the structure been solved already?Crystallographic Structure Databases

•(UK based academics and students already have free access via the EPSRC funded CDS (Chemical Database Service):

– http://cds3.dl.ac.uk/cds/cds.html

– Dutch equivalent is the CMBI at: http://www.cmbi.kun.nl/cheminf/

•ICSD (Minerals and Inorganics)– http://www.fiz-karlsruhe.de/

– Web accessible demonstration:

– http://barns.ill.fr/dif/icsd/

•MDF/CRYSTMET – (Metals and Alloys)

– http://www.tothcanada.com

•CCSD – (Organics and Organometallics)

– http://www.ccdc.cam.ac.uk/

•American Mineralogist – http://www.geo.arizona.edu/xtal-cgi/test/

•WWW Mincryst– http://database.iem.ac.ru/mincryst/

– 2398 unique phases - most with crystal structure data

•Mineral web – http://www.minweb.co.uk


ICSD via the Web

Using an Interface created by Alan Hewat at ILL, Grenoble, France

There is a trend for databases to use the web due to the convenience and effectiveness. Also has advantage of being operating system independent for users.

– http://barns.ill.fr/dif/icsd/


Structure Importing, Conversion and TransformationSummary list of available software at: http://www.ccp14.ac.uk/solution/structconv/

Be careful to check the resultsBest program for the moment is the shareware Cryscon

http://www.shapesoftware.com

Example of Cryscon for Windows by Eric Dowty


Powder Sample Preparation and Data Collection

–Assumption is that you know about appropriate sample preparation and data collection

–However, many hardware vendors might not provide the required flexibility in data collection


Variable Count Time data collection• Main idea here is to increase the raw intensity of selected peak areas to assist in the “required” analysis: (similar to what a CAD4 does)

– Up till now, if at all, mainly done for refinement (e.g., Hill and Madsen method)

• On point detector (e.g., Bragg Bretano flat plate system), do this by varying the count time in a pre-defined manner

– (Can also provide more time effective counting time)

Fixed Count Time Variable Count Time


VCT Literature References

"Collection and analysis of powder diffraction data with near-constant

counting statistics", I. C. Madsen and R. J. Hill, J. Appl. Cryst. (1994). 27, 385-392 http://www.iucr.org/cgi-bin/paper?hz0014

Philips Friendly Fortran source code that does this Hill and Madsen method is at: http://www.ccp14.ac.uk/ccp/ccp14/ftp-mirror/csirominerals-anon-ftp/pub/xtallography/variable-count-time/

(Original Hill and Madsen VCT (variable count time) Paper), I. C. Madsen and

R. J. Hill, Adv. X-ray Anal. (1992), 35, 39-47

W. I. F. David, Accuracy in Powder Diffraction, Abstract P2.6 NIST Special

Publication No. 846, Page 210, (1992) National Institute of Standards and Technology, Gaithersburg, MD, USA.


VCT for trace Phase ID (1 of x)

Fixed Count Time data (data collected by Jeremy Cockcroft)



Variable Count Time data (displayed as FCT)(data collected by Jeremy Cockcroft)



Fixed Count Time data (zoomed)



Variable Count Time data (displayed as FCT) (you only need to count excessively in the relevant angular ranges)


Variable Count Time applications

Equally relevant to problems where you need to adequately profile fit small / trace peaks which might not be significantly above background in a “routine”, time effective fixed count time data collection - e.g.,;

– Powder Indexing– Unit Cell refinement– Quantitative Rietveld Analysis


VCT to aid in phase ID and profile fitting (1 of 2)

Fixed Count Time


VCT to aid in phase ID and profile fitting (2 of 2) Variable Count Time

(you only need to count excessively in the relevant angular ranges)


VCT for Structure Solution and Refinement (1 of 4)

Variable Count Time data (as collected)



Variable Count Time data (displayed as FCT)



Variable Count Time data (displayed as VCT)


Where is VCT Data Collection?

Not a routine or available option in majority of commercial XRD control software

Something to keep an eye on - or request from vendors. VCT is in the new Bede powder diffraction system


Peak Profiling (indexing, unit cell refinement, size/strain, etc)

For Overall Summary of available peak profiling software refer to:

http://www.ccp14.ac.uk/solution/peakprofiling/

These include: CMPR, DRXWin, EFLECH, Fityk (GPL’d);GPLSFT, pearson.xls, SHADOW, Powder v2.00, PowderX, Winfit, Winplotr, XFIT

Examples of XFIT for Windows(includes fundamental parameters peak profiling)


Powder Indexing - a non trivial endeavour• For Overall Summary of available powder indexing software refer to:

http://www.ccp14.ac.uk/solution/indexing/• Powder Indexing: Autox, Ito, Dicvol, Treor, Taup/Powder, Lzon,

Losh, Kohl, Scanix, Xrayscan, EFLECH/Index, Supercell• Linking Suites: Crysfire, Powder v2.00, PowderX, PROSZKI,

WinPlotr, Chekcell

• supercel is a specialise indexing program by Juan Rodriguez-Carvajal for indexing Super Cell and Incommensurate cells. (available within Winplotr)

http://www-llb.cea.fr/winplotr/winplotr.htm

ftp://bali.saclay.cea.fr/pub/divers/fullprof.2k/


Powder Indexing - the “Crysfire” suite•At present the CRYSFIRE software by Robin Shirley links 8 different indexing programs (ito, dicvol, treor, taup, kohl, lzon, fjzn and losh) together with a common interface and using intelligent defaults. Important to have access to as many indexing programs as possible so you can get a feel for the range of possible solutions.

http://www.ccp14.ac.uk/tutorial/crys/

Example of CRYSFIRE Screen prompting the saving into one of 8 different indexing program formats:


Chekcell: Interpreting Crysfire Summary Files: Powder Indexing and Spacegroup Assignment

•Crysfire interlinks with Chekcell for Windows (part of the LMGP suite for Windows by Jean Laugier and Bernard Bochu). Chekcell provides a graphical interface for manually and automatically suggesting a best cell/spacegroup combination using both FOM and algorithms relating to parsimony of superfluous HKLs.

http://www.ccp14.ac.uk/tutorial/lmgp/


Chekcell : automatic cell and spacegroup searching

can trudge through a single selected unitcell; or over 1000s of trial cells looking for the best cell and spacegroup combination based on “parsimony of extra reflections” criteria.


Chekcell: “integration” of Ton Spek and A. Meetsma’s Le Page

•Obtaining the Reduced Cell

– which many powder indexing programs to not reliably determined

– Refer: "'Reduced Cells', M.J. Buerger, (Zeitschift fur Kristallographie, BD 109, S. 42-60 (1957)”

•Efficient Sub-cell and super-cell searching, then easy reviewing of newly derived cells within the Chekcell interface


Some Alternatives to Crysfire: Winplotr, PowderX

Winplotr by Juan Rodriguez-Carvajal– http://www-llb.cea.fr/fullweb/powder.htm

PowderX by Cheng Dong– http://www.ccp14.ac.uk/tutorial/powderx/

Powder v2 by Nita Dragoe– http://www.ccp14.ac.uk/tutorial/powder/

CMPR for Windows and UNIX by Brian Toby (with source code)

– http://www.ccp14.ac.uk/tutorial/cmpr/


New MCMaille by Armel Le Bail (Sep 2002)

by Armel Le Bail– http://www.cristal.org

Monte Carlo Cell finding / indexing software

Whole Profile method using reconstituted peaks positions and intensities

Not sensitive to trace impurities

Latest version can works almost as fast as Dicvol

Poor data can still give no reasonable result.


Updated MCMaille - December 2002Can “try” and index 2 phase materials

Very experimental “2 phase” desparation option

Could be far better to go back into the lab and try and separate out the phases

As it is distributed with the source code - you can make your own modifications and add features.


Unit Cell Refinement (powders)

•For Overall Summary of available unit cell refinement software refer to:

http://www.ccp14.ac.uk/solution/unitcellrefine/

•This includes:– Celref, LAPOD, Refcel, Unitcell, Eracel, Powder v2.00, XLAT, etc

•Can be helpful to perform a conventional unit-cell refinement prior to a Le Bail fit (or where unit weighting of each reflection is important).


CELREF for Unit Cell Refinement

•by Jean Laugier and Bernard Bochu http://www.ccp14.ac.uk/tutorial/lmgp/

•In this example, celref is performing graphical Unit Cell refinement on calcite in a multi-phase mixture

Knows about spacegroups

Graphics can really help sort out errors or misassigned hkls


Full Profile Fitting (Powder)

•For Overall Summary of available full profile analysis refer to:

Le Bail based: http://www.ccp14.ac.uk/solution/lebail/

Pawley Based: http://www.ccp14.ac.uk/solution/pawley/

•The most common method of full profile fitting is that of Le Bail fitting: which is in most Rietveld packages. It is useful for:

– Spacegroup Assignment

– Unit Cell Refinement (especially when overlap is a problem)

– Extracting Intensities for Structure Solution


Le Bail full profile fitting - Rietica Rietveld

•By Brett Hunter– http://www.rietica.org– http://www.ccp14.ac.uk/tutorial/lhpm-rietica/

•Easy to use and setup via GUI

•Le Bail is Structureless whole profile fitting - just need cell and spacegroup

•Easy to add and delete structures

•Auto-marquardt damping for initial unstable refinement if required


Le Bail full profile fitting - Rietica Rietveld - 2 of 2

• In this example multiphase system where the aim is to get accurate unit cell volumes.

• No completely freestanding peak for KCl


Unit Cell Refinement: Mass Le Bail fitting: multi-phase - overlapping patterns

Using Le Bail fitting Using Traditional Methods


Materials Analysis Rietveld/Texture Software• Pole Figure, Texture Analysis –

important also for some forms of Le Bail fitting and structure solution from powders

• Summary List of available software:• http://www.ccp14.ac.uk/solution/pole_figure/

– BEARTEX for Windows

– GSAS Rietveld (Windows/UNIX)

– MAUD for Java

– POFINT

– popLA

– Symmet for DOS

– TexturePlus for Windows

MAUD (for Java PC/Mac/UNIX)Crystallite size and shape analysis

http://www.ing.unitn.it/~luttero/


Solving Structures: Single Crystal vs Powder diffraction (1 of 5)

Single Crystal• “Mass transit” structure

solution and refinement

• There are difficulties:– Crystal not representative

of the bulk

– Twinning

– Crystal decomposes during data collection

– “Difficult” structure


Single Crystal vs Powder diffraction (2 of 5)

Cambridge Database• (that Scale is in the 100’s of thousands)

– 2001 report: http://www.ccdc.cam.ac.uk/about/annrep2001/report.html

– http://www.ccdc.cam.ac.uk/prods/csd/csd.html



ICSD Database (inorganics - and minerals)

• During first 6 months of 2002, 3073 new entries were added.

• July 2002 ICSD release : a total of 64,848 entries

ICSD entries by date of publication

0

500

1000

1500

2000

2500

3000

1 9 17 25 33 41 49 57 65 73 81 89 97

Year (19xx)

Pu

blic

atio

ns

Cumulative ICSD entries by date of publication

0

10000

20000

30000

40000

50000

60000

70000

1 9 17 25 33 41 49 57 65 73 81 89 97

Year (19xx)

Pu

blic

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Powder Methods for solving structures• A nightmare to some

• An adventure to others!



Number of structures solved by powder methods

• 592 up to end of 2001

• http://sdpd.univ-lemans.fr/iniref.html• http://sdpd.univ-lemans.fr/iniref/SDPD-activity.html


Structure Solution from Powder Diffraction Round Robins1st SDPD Round Robin - 1998:

(Solving only): http://www.cristal.org/SDPDRR/

• Solving:• 70 Downloads of data

• Only two submissions using:– CSD System from Stoe

– Druid/Mystic (now called Dash)

2nd SDPD Round Robin - 2002:

(Indexing and solving): http://www.cristal.org/sdpdrr2/

• Indexing:– Only 6 submissions (6% return rate)

– Only Index/EFLECH by Joerg Bergmann was able to suggest solutions for samples 4 to 8 within the time limit.

• Solving:• >100 Downloads of data

• Only two submissions using:– Fox (GPL’d - free)

– Topas (commercial from Bruker)


“Generic” structure solution from powder diffraction data• Very non-trivial endeavour.

• (though indexing can often be the limiting step in many attempted structure solutions)

• EXPO - Direct Methods (Sirware Group) Makers of Sir92/Sir97/Sirpow

– http://www.irmec.ba.cnr.it/

• If EXPO fails, it is possible to use Le Bail or Pawley extracted data with Single Crystal Structure Solution Software:

– http://www.ccp14.ac.uk/solution/xtalsolution/

• Then consider real space methods such as using ESPOIR (GPL’d by Armel Le bail) or FOX (GPL’d by Vincent Favre-Nicolin and Radovan Cerny) - normally real space methods use as last resort:

– ESPOIR: http://sdpd.univ-lemans.fr/sdpd/espoir/– Web tutorial on setting up the ESPOIR files in < 10 minutes" and example of solving on an

organic molecule: http://sdpd.univ-lemans.fr/sdpd/espoir/10mn/

– FOX: http://objcryst.sourceforge.net/


“Specialised and Commercial” Structure Solution Programs

• PSSP – molecular structures – http://powder.physics.sunysb.edu/programPSSP/pssp.html

• ZEFSA II – for Zeolites (GPL’d) – http://www.mwdeem.rice.edu/zefsaII/

• Focus – for Zeolites

– http://www.kristall.ethz.ch/LFK/software/• Fullprof – Monte Carlo for structure solution and finding Magnetic Moments in neutron data

– ftp://bali.saclay.cea.fr/pub/divers/winplotr/

• “Available” Commercial Structure Solution from Powder Diffraction Data software:– Powder Solve: http://www.accelrys.com

– Crystal Structure Determination Package (WinCSD/CSD) : http://imr.chem.binghamton.edu/zavalij/CSD.html

– DASH (Druid and Mystic of old): http://www.ccdc.cam.ac.uk/prods/dash/

– TOPAS : http://www.bruker-axs.com

– Endeavour : http://www.crystalimpact.com/endeavour/


New FOX real space structure solution by Vincent Favre-Nicolin and Radovan Cerny

Available for UNIX/Linux and MS-Windows

GUI Based

Is friendly in setting up of rigid bodies

Includes automatic merging of atoms on special position with dynamic occupancy correction

http://objcryst.sourceforge.net/


Adding polyhedra in Fox - 1 of 5

Click on “Crystals”, “Scatterers” Icon, “Add”



Select the central atom



Select the corner atom(s)



Give the Bond length



Done!


Structure Refinement using Powder Diffraction Data(Rietveld Refinement)

• Large range of programs to choose from:

– http://www.ccp14.ac.uk/mirror/mirror.htm

– http://www.ccp14.ac.uk/solution/rietveld_software/

• Many specialize for particular types of problems, incommensurate structures, quantitative analysis, polymers, etc.

• ARITVE, BGMN, DBWS, DEBVIN, EXPO

• Fullprof, GSAS, Koalariet, LHPM-Rietica, MAUD for Java (GPL’d)

• Premos/Remos, ProDD, Profil, Quanto, Riet7/SR5, Rietan 2000 (GPL’d)

• Rietquan, Simref, WinMprof, XND, XRS-82/DLS-76


Rietveld Program Interfaces Not yet as robust and powerful as

single crystal refinement programs (Single Crystal programs are very poweful and do a lot for the user)

Unlike most single crystal suites, you are not interacting directory with the structures on the screen.

Many choose their Rietveld based on what the people down the road are using. Not only human nature but learning a Rietveld program from scratch can be difficult.

• Interfaces into Rietveld programs vary from GUIs to direct editing of ASCII files.


Rietveld Programs - Rietica by Brett Hunter Full Graphical User Interface Still got to appreciate and know your crystallography for inserting and

refining the crystal structure http://www.rietica.org


Mentioning GSAS Rietveld: Some Relevant Background

• by Bob von Dreele and Alan Larsen

• Menu based control

• Available for Windows / DOS / Linux / SGI

• Separate GUI by Brian Toby (EXPGUI)

• Combined X-ray / Neutron / Single Crystal / Powder Diffraction

• Integrated Fourier map generation and viewing

• GSAS resources, tutorials and links (including links to EXPGUI)– http://www.ccp14.ac.uk/solution/gsas/

• Restraints– Bond angle

– Bond length

– Planar

– Total Chemistry / charge balance

– Chiral volume

– Phi/psi group

– Torsion angle

• Manual Marquadt damping

• Atom shift limits

• Lots of other features


GSAS : Solving and refining a protein from powder data

• As cited in R. B. Von Dreele, P. W. Stephens, G. D. Smith and R. H. Blessing, "The first protein crystal structure determined from high-resolution X-ray powder diffraction data: a variant of T3R3 human insulin-zinc complex produced by grinding", Acta Cryst. (2000).

D56, 1549-1553.

http://journals.iucr.org/d/issues/2000/12/00/issconts.html


Brian Toby’s EXPGUI Interface for GSAS

User friendlier to start using GSAS via EXPGUI(A new combined installer makes it very easy to start using GSAS.)

http://www.ncnr.nist.gov/programs/crystallography/software/expgui/expgui_intro.html


Restrained Rietveld structure refinement of organics

• Software not as powerful as single crystal but there are some tutorials with tricks on the CCP14 website

http://www.ccp14.ac.uk/solution/restrained_rietveld/


Fourier capability in Rietveld Software

Example of GSAS2D contour maps and also VRML output (below)

Summary list of Fourier friendly Rietveld software at: http://www.ccp14.ac.uk/solution/rietveld_fourier_maps/


Some Specialist Applications

• Anharmonic Refinement

– List of Software:

– http://www.ccp14.ac.uk/solution/anharmonic/

• Incommensurate Structure Refinement


– http://www.ccp14.ac.uk/solution/incomm.htm

• PDF / High Q Analysis


– http://www.ccp14.ac.uk/solution/high_q_pdf/


Quantitative Phase Analysis• Non-trivial and in many cases,

custom solutions may be required. (accurate Quantitative analysis is a complete world in itself)

• Rietveld programs are commonly used for Quantitative Analysis (refer list in a previous slide).

• Refer to non-Rietveld references cited in:

Following using Koalariet / XFIT(fundamental parameters)

http://www.ccp14.ac.uk/tutorial/xfit-95/

http://www.ccp14.ac.uk/poster-talks/david-hay-quant-notes-axaa99/


MAUD for Java : GPL’d (you get the source code)

Tutorial on “Performing an x-ray quantitative analysis in seven easy steps!”:

http://www.ing.unitn.it/~luttero/maud/tutorial/

http://www.ccp14.ac.uk/ccp/web-mirrors/lutterotti/~luttero/maud/tutorial/

Including options for standardless quantitative analysis on amorphous material


New for 2002: Fullpat (runs within MS-Excel)By Steve Chipera and Dave Bish of Los Alamos National Laboratory, USA

http://www.ccp14.ac.uk/ccp/web-mirrors/fullpat/

Full profile non-Rietveld method using standards

Described in the IUCr Commission on Powder Diffraction Newsletter:

http://www.se.iucr.org/iucr-top/comm/cpd/Newsletters/no27jul2002/


Quantitative Phase Analysis - is it routinely easy?

Based on the IUCr CPD Quant Round Robin(http://www.iucr.org/iucr-top/comm/cpd/QARR/)

The answer seems to be No!A quote from Armel Le Bail’s Tmacle “twinned refinement” software manual seems appropriate:

http://sdpd.univ-lemans.fr/museum/tmacle92.zip

GOOD LUCK IT'S VERY HARD! DON'T YOU THINK SO?ONLY THE BOSS SAID THAT IT IS EASY, BUT HE NEVER TRIED!


Graphically interacting with the structure• Number of programs available with

list available at:http://www.ccp14.ac.uk/solution/structuredrawing/

• Most single crystal suites include structure viewing by default but not powder refinement programs

• Some can read common file formats (CIF, Shelx, etc)

– Gui WinORTEP reads the widest variety of formats

• Software includes: Crystals, Cameron, PIG (part of the Xtal suite), ORTEX, Gretep, Platon, GUI WinORTEP, GUI WinSTRUPLO

Gretep by Jean Laugier and Bernard Bochuhttp://www.ccp14.ac.uk/tutorial/lmgp/#gretep


Validation - why take an interest?• For perhaps the same reason that Columbia University

Law/Journalism professors teach their students (at least one - circa late

1940’s):

“If your mother says she loves you,”

“CHECK IT OUT!!”

• If you want to publish anything that can stand the test of time - you need to be validating your results as much as possible.


Platon’s Addsym (by Ton Spek): checking for extra symmetry : e.g., Structure Published in 1997

P1 - Triclinic: 42 non-H atoms


Platon’s Addsym: Correction Published in 1999: C2 - Monoclinic: 22 non-H atoms


Platon’s Addsym: Press of a button: 2000: FDD2 - Orthorhombic: 11 non-H atoms

(Short Communication Abstract: "P1 or P-1? Corrigendum", Acta Cryst B56 (2000) 744 from Richard E. Marsh)


Platon’s Addsym: for powders • Some powder based structures at the Royal Institution

and Birkbeck College in London solved using EXPO direct methods

• Triclinic P 1 - found by Addsym to be P -1

• Orthorhombic:

– P 21 21 21 - found by Addsym to be P n m a– P 2 21 21 - found by Addsym to be P m m n

• Platon is not free for commercial use


Powder diffraction pattern calculationPowder Cell for Windows

• Most Rietveld Programs can calculate powder patterns but they may not be all that friendly to use

• Two dedicated GUI programs for calculating powder patterns - 1st being:

• Powder Cell by Werner Kraus and Gert Nolze at BAM in Germany

http://www.ccp14.ac.uk/tutorial/powdcell/


Powder diffraction pattern calculationPoudrix for Windows

• Powder Cell by Jean Laugier and Bernard Bochu

http://www.ccp14.ac.uk/tutorial/lmgp/#pdw

• Poudrix can handle anomalous dispersion at non X-ray tube wavelengths with the option of two models:

– Brenann and Cowan

– Sasaki


Photorealistic hardcopy output of structuresUsing GRETEP by Jean Laugier and Bernard Bochu

http://www.ccp14.ac.uk/tutorial/lmgp/http://www.ccp14.ac.uk/ccp/web-mirrors/lmgp-laugier-bochu/


Freeware for photorealistic hardcopy output of structures

Balls and Sticks by Sung J. Kang & Tadashi C. Ozawa

• http://www.toycrate.org• http://www.ccp14.ac.uk/ccp/web-mirrors/toycrate/

• Individual point and click creation of polyhedra and bonds via a Windows graphical user interface


Photorealistic hardcopy output of Fourier MapsMarching Cubes by Michal Husak

(http://www.ccp14.ac.uk/tutorial/marchingcube/)

• Interlinks with WinGX, Crystals and can read Project XD files. Software for converting GSAS Fourier files is available.


Other Internet Resources

• Crystallographic Mailing lists and internet newsgroups:– http://www.ccp14.ac.uk/maillist/

– Including:• Sci.techniques.xtallography Internet newsgroup

• Rietveld Users’ Mailing List

• SDPD - Structure Determination from Powder Diffractometery

• XRD - discussions on X-ray Diffraction Hardware

• Clay Minerals Mailing List

• IUCr Commission on Powder Diffraction Newsletter:– http://www.iucr.org/iucr-top/comm/cpd/Newsletters/


Dual Boot UNIX / Windows PC and Crystallographic Nexus CD-ROMs for those isolated from the internet

• Tutorials for creating dual boot Windows / UNIX PCs:

• Linux– refer: http://www.ccp14.ac.uk/solution/linux/

• FreeBSD (can run linux binaries)– refer: http://www.ccp14.ac.uk/solution/bsdunix/

• (be careful of hackers invading your systems when running Linux/UNIX. CCP14 tutorials try to be security conscious and leave no “open” services)

• Free Xtal Nexus CD-ROMs for academics and students

• http://www.unige.ch/crystal/stxnews/nexus/index.htm

• (Supported & Sponsored by the IUCr and CCP14)

• Contact the author (Lachlan Cranswick) for a freeair-mailed CD-ROM.


Don’t be a “passive kitten” Just looking over someone’s shoulder will not teach you how to use this

software. You have to use it yourself on your real scientific problems.

Image from: http://www.cs.umbc.edu/~rheingan/SIGGRAPH/motion.slides.pdf


Summary

Large Genetic Diversity of Software This diversity is necessary to help you get the job done. Getting better all the time (some areas faster than others) Freely available for Academics and Students

Much is free for commercial applications

• Downloadable via the EPSRC funded CCP14 website:

http://www.ccp14.ac.ukE-mail: [email protected]