Determining complex crystal structures from high pressure single-crystal diffraction data collected on synchrotron sources

2013 ◽  
Vol 33 (3) ◽  
pp. 485-500 ◽  
Author(s):  
M. I. McMahon ◽  
I. Loa ◽  
G. W. Stinton ◽  
L. F. Lundegaard
2013 ◽  
Vol 46 (2) ◽  
pp. 387-390 ◽  
Author(s):  
Hui Li ◽  
Xiaodong Li ◽  
Meng He ◽  
Yanchun Li ◽  
Jing Liu ◽  
...  

High-pressure single-crystal diffraction experiments often suffer from the crushing of single crystals due to the application of high pressure. Consequently, only diffraction data resulting from several particles in random orientations is available, which cannot be routinely indexed by commonly used methods designed for single-crystal data. A protocol is proposed to index such diffraction data. The techniques of powder pattern indexing are first used to propose the possible lattice parameters, and then a genetic algorithm is applied to determine the orientation of the reciprocal lattice for each of the particles. This protocol has been verified experimentally.


2005 ◽  
Vol 7 (11) ◽  
pp. 1363-1368 ◽  
Author(s):  
Stanislav Filatov ◽  
Nikolay Bendeliani ◽  
Barbara Albert ◽  
Jürgen Kopf ◽  
Tatiana Dyuzeva ◽  
...  

2015 ◽  
Vol 70 (4) ◽  
pp. 207-214 ◽  
Author(s):  
Daniela Vitzthum ◽  
Stefanie A. Hering ◽  
Lukas Perfler ◽  
Hubert Huppertz

AbstractOrthorhombic dysprosium orthogallate DyGaO3 and trigonal gallium orthoborate GaBO3 were synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 8.5 GPa/1350 °C and 8 GPa/700 °C, respectively. Both crystal structures could be determined by single-crystal X-ray diffraction data collected at room temperature. The orthorhombic dysprosium orthogallate crystallizes in the space group Pnma (Z = 4) with the parameters a = 552.6(2), b = 754.5(2), c = 527.7(2) pm, V = 0.22002(8) nm3, R1 = 0.0309, and wR2 = 0.0662 (all data) and the trigonal compound GaBO3 in the space group R3̅c (Z = 6) with the parameters a = 457.10(6), c = 1419.2(3) pm, V = 0.25681(7) nm3, R1 = 0.0147, and wR2 = 0.0356 (all data).


ChemInform ◽  
2006 ◽  
Vol 37 (6) ◽  
Author(s):  
Stanislav Filatov ◽  
Nikolay Bendeliani ◽  
Barbara Albert ◽  
Juergen Kopf ◽  
Tatiana Dyuzeva ◽  
...  

2007 ◽  
Vol 62 (6) ◽  
pp. 765-770 ◽  
Author(s):  
Holger Emme ◽  
Gunter Heymann ◽  
Almut Haberer ◽  
Hubert Huppertz

The compounds β -RE(BO2)3 [RE = Nd (neodymium meta-borate), Sm (samarium meta-borate) and Gd (gadolinium meta-borate)] were synthesized under high-pressure and high-temperature conditions in a Walker-type multianvil apparatus at 3.5 GPa (Nd), 7.5 GPa (Sm, Gd) and 1050 °C. The crystal structures were determined by single crystal X-ray diffraction data collected at r. t. (Sm, Gd) and at−73°C (Nd), respectively. The structures are isotypic with the already known ambient-pressure phases β -RE(BO2)3 (RE = (Tb, Dy) and the high-pressure phases β -RE(BO2)3 (RE = Ho-Lu)


2013 ◽  
Vol 33 (1) ◽  
pp. 196-201 ◽  
Author(s):  
K. Friese ◽  
A. Grzechnik ◽  
J. M. Posse ◽  
V. Petricek

2009 ◽  
Vol 64 (9) ◽  
pp. 1032-1040 ◽  
Author(s):  
Stefanie A. Hering ◽  
Hubert Huppertz

Monoclinic holmium sesquioxide B-Ho2O3 and orthorhombic holmium orthogallate HoGaO3 were synthesized in a Walker-type multianvil apparatus under high-pressure / high-temperature conditions of 11.5 GPa / 1250 °C and 7.5 GPa / 1250 °C, respectively. Both crystal structures could be determined by single-crystal X-ray diffraction data, collected at r. t. The monoclinic holmium oxide crystallizes in the space group C2/m (Z = 6) with the parameters a = 1394.7(3), b = 350.83(7), c = 865.6(2) pm, β = 100.23(3)°, R1 = 0.0517, wR2 = 0.1130 (all data), and the orthorhombic compound HoGaO3 in Pnma (Z = 4) with the parameters a = 553.0(2), b = 753.6(2), c = 525.4(2) pm, R1 = 0.0222, and wR2 = 0.0303 (all data).


2018 ◽  
Vol 233 (7) ◽  
pp. 501-506
Author(s):  
Andrei V. Mironov ◽  
Victor A. Tafeenko ◽  
Dmitrii Yu. Grebenkin ◽  
Alexander E. Oblezov

Abstract The crystal structures of 6-methyl-2-ethyl-3-hydroxypyridiniun nitrate (C8H12NO)NO3 (I) and fumarate (C8H12NO)2C4H2O4 (II) were solved and refined from X-ray single crystal diffraction data (CuKα, (I) a=4.6477(2), b=14.5906(9), c=14.5551(8) Å, β=99.100(4)°, space group P21/c, Z=4, Rp/Rwp=0.033/0.047; (II) a=8.8293(3), b=13.4268(5), c=8.3893(3) Å, β=96.303(3)°, space group P21/c, Z=2, Rp/Rwp= 0.034/0.049). Both structures are built of infinite chains along ac diagonal of the unit cells formed by hydrogen bonding between the hydroxypyridium cation and the corresponding anion. Each fumarate anion is linked to four hydroxypyridium cations while nitrate anion is connected with two hydroxypyridium cations only leaving one oxygen atom in the nitrogen group isolated.


2008 ◽  
Vol 23 (4) ◽  
pp. 307-316 ◽  
Author(s):  
Nickolay A. Tumanov ◽  
Elena V. Boldyreva ◽  
Hans Ahsbahs

The structure of a high-pressure polymorph of glycine (the β′-polymorph formed reversibly at 0.8 GPa from the β-polymorph) was determined from high-resolution X-ray powder diffraction data collected in situ in a diamond anvil cell at nine pressure points up to 2.6 GPa. X-ray powder diffraction study gave a structural model of at least the same quality as that obtained from a single-crystal diffraction experiment. The difference between the powder-diffraction and the single-crystal models is related to the orientation of the NH3-tails and the structure of the hydrogen-bonds network. The phase transition between the β- and β′-polymorphs is reversible and preserves a single crystal intact. No transformations were observed between the β-, α-, and β′-polymorphs on compression and decompression, although the α- and β′-polymorphs belong to the same space group (P21/c). The instability of the β- and γ-forms with pressure can be predicted easily when considering the densities of their structures versus pressure. The direction of the transformation (i.e., which of the high-pressure polymorphs is formed) is determined by structural filiation between the parent and the high-pressure phases because of the kinetic control of the transformations.


2009 ◽  
Vol 64 (5) ◽  
pp. 491-498 ◽  
Author(s):  
Stephanie C. Neumair ◽  
Hubert Huppertz

Fe2B2O5, synthesized under mild high-pressure / high-temperature conditions of 3 GPa and 960 ◦C, possesses a structure isotypic to the triclinic pyroborates M2B2O5 with M = Mg, Mn, Co, and Cd. Although the parameter pressure is not essential to the synthesis of Fe2B2O5, the specific conditions enhance the crystallinity of the product. Therefore, the crystal structure of the iron pyroborate Fe2B2O5 could be determined via single crystal diffraction data [space group P1̄ (Z = 4) with the parameters a = 323.1(1), b = 615.7(2), c = 935.5(2) pm, α = 104.70(3), β = 90.82(3), γ = 91.70(3)◦, V = 0.1799(1) nm3, R1 = 0.0409, and wR2 = 0.0766 (all data)]. The structure is built up from layers of isolated pyroborate units ([B2O5]4−), which are composed of two corner-sharing BO3 triangles. These pyroborate layers serve to bridge 4×1 ribbons of edge-sharing FeO6 octahedra by both edgeand corner-sharing.


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