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Jana2006
Institute of Physics, Prague 6, Cukrovarnická street
Jana2006
Program for structure analysis of crystals periodic in three or more dimensions from diffraction data
Václav Petříček, Michal Dušek & Lukáš Palatinus Institute of Physics, Prague, Czech Republic
Which part of the cake you can have with Jana?
Small molecules in service crystallography
Minerals
Proteins
Locally ordered structures (diffuse scattering) Modulated and composite structures
Quasicrystals
Magnetic structures
Microcrystals by electron diffraction Nanomaterials
Thin layers
History 1980 SDS Program for solution and refinement of 3d structures
1984 Jana Refinement program for modulated structures
1994 SDS94 and Jana94 Set of programs for 3d (SDS) and modulated (Jana) structures running in text mode.
1996 Jana96 Modulated and 3d structures in one program. Graphical interface for DOS and UNIX X11.
1998 Jana98 Improved Jana96. First widely used version. Graphical interface for DOS, DOS emulation and UNIX X11
2000 Jana2000 Support for powder data and multiphase refinement. Graphical interface for Win32 and UNIX X11.
2006 Jana2006 Combination of data sources, magnetic structures, TOF data. Dynamical allocation of memory. Only for Windows.
Where to start?
Data input
Single crystal data of one or more domains OR
X-rays OR neutrons OR electrons
Powder data of one or more phases
Import Wizard
Data Repository
Format conversion, cell transformation, sorting reflections to twin domains
M95 + M50
M90
M40
Single crystals: determination of symmetry, merging symmetry equivalent reflections, absorption correction
Solution (by calling external programs)
Refinement or Rietveld refinement Transformation Introduction of twinning Change of symmetry
M95 data repository M90 refinement reflection file M50 basic crystal information, form factors, program options M40 structure model
Plotting, geometry parameters, Fourier maps ….
Program Scheme Reading of one or more data sets. Powders must be indexed by an external program.
Powders: Le Bail refinement of profile parameters
M41 Extraction of intensities, determination of symmetry
Reading of data: M95 + M50 Determination of symmetry: M50
Merging of symmetry equivalent reflections, application of extinction rules: M90 Le Bail refinement of powder profile: M41 Structure solution: M40
Structure refinement: M40 Transformations Structure plots
Charge flipping
Topics Basic crystallography Advanced tools Incommensurate structures Commensurate structures Composite structures Magnetic structures Jana2006 is old fashioned: written in Fortran; not using external libraries (except basic graphics); not written by a team of programmers → flexibility NOT included in Jana2006: Phase problem solution: calls SIR97,2000,2004; EXPO, EXPO2004, Superflip Plotting: calls Diamond, Vesta, MC (marching cube) and other plotting software Validations and geometry analysis: relies on Platon
Basic crystallography Wizards for symmetry determination External calls to Charge flipping and Direct methods Tools for editing structure parameters Tools for adding hydrogen atoms Constrains, Restrains Fourier calculation Plotting (by an external program) CIF output Under development: graphical tools for atomic parameters, CIF editor
Advanced tools common for 3d and modulated structures
Fourier methods Transformation tools, group-subgroup relations Twinning (merohedric or general), treating of overlapped reflections User equations and restrictions Disorder and “Rigid body” approach Anharmonic ADP Multiphases for both powder and single crystal data Multipole refinement Powder data: Anisotropic strain broadening (generalized to satellites) Fundamental approach TOF data Local symmetry
Twinning (pseudo-merohedric three-fold twin)
−−−
−
−
−
21
23
21
21
21
23
21
21
00
001
00
001
Twinning matrices for data indexed in hexagonal cell:
Disorder and rigid bodies
Disorder of tert-butyl groups in N-(3-nitrobenzoyl)-N', N"-bis (tert-butyl) phosphoric triamide. The groups were described like split “rigid” bodies. One of rigid body rotation axis was selected along C-N bond in order to estimate importance of rotation along C-N for description of disorder.
Anharmonic description of ADP (ionic conductor Ag8TiSe6)
Plot: Jana calculates electron density map and calls Marching Cube.
Local icosahedral symmetry for atom C of C60 Powder data, (J.Appl.Cryst. (2001). 34, 398-404)
Local symmetry
View along a ◄Lindströmite
View along a Krupkaite ►
Single crystal multiphase systems
Modulated structures very short explanation what does it mean
Sodium carbonate View along c z from 0 to 1
Sodium carbonate View along c z from 1 to 2
Sodium carbonate View along c z from 2 to 3
Is there some translation periodicity? Probably yes because the diffraction pattern looks like usually
c*
a*
…. but we cannot describe all peak positions with a lattice
c*
a*
c*
a*
* * *1 2 3q q q= + +q a b c
The remaining spots can be described with q-vector, which has irrational components. Indices h k l m
Four-dimensional reciprocal lattice Modulated and composite crystals can be described in a (3+d) dimensional superspace. The theory has developed by P.M.DeWolff, A.Janner and T.Janssen (Aminoff prize 1998). The basic idea: real diffraction pattern is a projection from the (3+d) dimensional superspace. The basic assumption: all satellites are clearly separated. (the intensities diminish for large satellite index).
e q
*4A
*3
*3 Aa =*3a
*3R
Modulation function
The atom is displaced from its basic position by a periodic modulation function that can be expressed as a Fourier expansion. In the first approximation intensities of satellites reflections up to order m are determined by modulation waves of the same order.
( ) ( ) ( )4 , 4 , 41 1
sin 2 cos 2m m
s n c nn n
x nx nxπ π= =
= +
= +∑ ∑
r r u
u A A
e=A4
Basic position
incommensurate
Incommensurate structures Modulation of occupation, position and ADP Traditional way of solving from arbitrary displacements Solving by charge flipping Modulation of anharmonic ADP Modulation of Rigid bodies including TLS parameters Special functions Fourier sections Plotting of modulated parameters as a function of t Plotting of modulated structures Calculation of geometric parameters
Natural melilite from San Venanzo, Umbria, Italy Formula: (Ca1.89Sr0.01Na0.08K0.02)(Mg0.92Al0.08)(Si1.98Al0.02)O7
Charge Flipping (Superflip of Lukas Palatinus)
The twinning matrix is 3x3 matrix regardless to dimension. Twinning may decrease dimension of the problem. Example: La2Co1.7, Acta Cryst. (2000). B56, 959-971. Average structure: 4.89 4.89 4.34 90 90 120 , P63/mmc Modulated structure: modulated composite structure, C2/m(α0β), 6-fold twinning around the hexagonal c
Reconstruction of (h,k,1.835) from CCD measurement.
Twinning of modulated structures
Disorder in modulated structures Cr2P2O7, incommensurately modulated phase at room temperature
Cr1 (0.500000 -0.187875 0.000000) Δ[Cr1] = 1 New atom: Cr1a (0.47, -0.187875 0.03) t40[Cr1a] = t40[Cr]+0.5* Δ[Cr1] Δ'[Cr1] = Δ[Cr1] - x Δ[Cr1a] = x New parameters for refinement: x and position of Cr1a Temperature parameters of Cr1a can be put equal to Cr1. No modulation can be refined for Cr1a. Analogically one can split positions of P1, O2 and O3. Refinement is very difficult, the changes should be done simultaneously.
Commensurate structures
Example of six-fold commensurate structure
Superspace description: 4d cell, atomic position + modulation function, superspace symmetry Supercell description: 3d six-fold supercell, atomic positions in six cells, 3d symmetry Both description are equivalent. Jana2006 can automatically transform commensurate structure to 3d structure in a supercell Origin of R3 section may influence symmetry in the supercell. Jana2006 can automatically find all possible supercell symmetries.
Superspace Supercell
This angle follows from q-vector
Exact intersection
Commensurate families In this example known M2P2O7 diphosphates are derived from the same superspace symmetry.
Composite structures
Hexagonal perovskites Two hexagonal subsystems with common a,b but incommensurate c.
c2
c1
( )
WHH
q
2=
=
==
1
12
,
0100100000100001
,0,0
W
ccγγ
q is closely related with composition
Typical Fourier section ►
Modulated structure of Sr14/11CoO3 q = 0.63646(11) ≈ 7/11 Acta Cryst. (1999). B55, 841-848
Magnetic structures
( ) ( ) ( ) ( )
( ) ( ) ( )[ ]
( ) ( ) ( )hhh
hFhhFh
rS
rhShhF
MN
MMM
i
i
i
i
iiiiiM
III
hI
Tf
iThfp
+=
⋅−=
∑ ⋅=
:intensity Total
:ndiffractiomagnetic of Intensity positionatomic
momentmagnetic
factor etemperaturfactor formmagnetic
:factor structureMagnetic
22
2exp
π
The distribution of the magnetic moments over the nuclear structure can be described by a modulation wave:
( ) ( ) ( )[ ]∑=
++=N
nikcinsii nxnxx
14404 2cos2sin ππ SSSS
Future development (Jana2012?) Electron diffraction Interface Documentation (hard to believe) Input of data
Solution
Refinement
Editing of structure model
Transformations
Fourier calculation and interpretation
External plotting
Calculation of geometry
CIF output
Plotting of modulated parameters
User support jana.fzu.cz
KAsF4(OH)2
Still freeware …. (the driving force are citations)
Jana2006 is continuously supported by Academy of Sciences of the Czech Republic and (occasionally) by (unpredictable) Grant agency of the CR
SHELX or Jana2006?
SHELX:
+ Everything written in SHELX is automatically accepted by IUCr and included in Platon. Therefore publication of structures is easier.
+ Many other programmers write tools for SHELX
+ Well developed geometry constraints for small molecules
- Unfriendly, old fashioned, no real development (excluding proteins), no communication with ordinary users, weak support for complicated structures
Jana2006:
+ much more possibilities for difficult structures
+ many methods supported by the same program
+ fast development, intensive and friendly communication with every user
- See “+” od SHELX
Jana2006 Tutorial in Uberlandia Session 1 Simple structure from single crystal data Disordered structure from single crystal data
Session 2 Simple structure from powder data Simple structure from powder data with asymmetric profiles
Session 3 Pseudomerohedric twin Twin with partial overlaps of diffraction spots
Session 4-5 Three-fold twin modulated structure powder structure described with rigid body
Data import Determination of symmetry Charge flipping Anisotropic ADP Hydrogens to carbon Hydrogens to nitrogen
Simple structure from single crystal data
2-fold supercell
3-fold supercell
statistical disorder: no structured diffuse scattering partial ordering -> structured diffuse scattering
Disordered structure from single crystal data
splitting positions with large ADP
Refined occupancies and distances to copper indicate that C4 and C6 are probably nitrogen, C6’ is probably carbon and in the position of C2 two atoms are coinciding
R=1.8%
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