Structural Science

 

Acta Cryst. (2012). B68, 559-570  [ doi:10.1107/S0108768112039961 ]

Structural transformation of Sb-based high-speed phase-change material

T. Matsunaga, R. Kojima, N. Yamada, Y. Kubota and K. Kifune

Synopsis: On heating, amorphous Ag_3.1In_3.7Sb_76.4Te_16.5 crystallizes at 416 K in an A7 structure type with atomic sites randomly occupied by the four constituent elements. At 545 K the compound decomposes into two crystalline phases: AgInTe₂ is stable up to the melting point, while Sb₈₉Te₁₁ has a modulated layer structure with a temperature-dependent layer period.

B-IncStrDB reference: 6732EXfQbW

Online 23 October 2012

 

Acta Cryst. (2012). B68, 571-577  [ doi:10.1107/S0108768112039274 ]

On the structural relations of malachite. II. The brochantite MDO polytypes

F. Girgsdies and M. Behrens

Synopsis: The crystal structures of malachite and brochantite are shown to be composed of topologically equivalent building blocks, which are also involved in the brochantite polytypism.

Online 23 October 2012

 

Acta Cryst. (2012). B68, 578-589  [ doi:10.1107/S0108768112041134 ]

Comparative structural study of decagonal quasicrystals in the systems Al-Cu-Me (Me = Co, Rh, Ir)

P. Kuczera, J. Wolny and W. Steurer

Synopsis: Comparative structural study of the decagonal quasicrystals of the Al-Cu-Me (Me = Co, Rh, Ir) family.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 590-601  [ doi:10.1107/S0108768112044217 ]

Mode-crystallography analysis and magnetic structures of SrLnFeRuO₆ (Ln = La, Pr, Nd) disordered perovskites

E. Iturbe-Zabalo, O. Fabelo, M. Gateshki and J. M. Igartua

Synopsis: The orthorhombic crystal structures of SrLnFeRuO₆ (Ln = La, Pr, Nd) form through distortions of the cubic perovskite structure type by two out of a possible five normal modes. Canted antiferromagnetic or ferrimagnetic order is found at low temperatures.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 602-609  [ doi:10.1107/S0108768112042577 ]

Dinuclear oxofluorometallates as a new structural type of d⁰ transition metal oxofluoride compound

A. A. Udovenko and N. M. Laptash

Synopsis: Two kinds of dimers in the crystal structures of A₃[M₂O_xF_11 - x]·(AF)_0.333 (A = K, Rb, NH₄; M = Nb, Mo, W; x = 2, 4) representing a new structural type of d⁰ transition metal oxofluoride compound are reported.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 610-618  [ doi:10.1107/S0108768112043996 ]

Structures from MnX₂ and proline: isomorphous racemic compounds and a series of chiral non-isomorphous chain polymers

K. Lamberts and U. Englert

Synopsis: The crystal chemistry of manganese(II) halides with racemic and enantiopure proline has been systematically explored. The reaction with an enantiopure amino acid results in three different chain polymers whereas racemic proline gives mononuclear isomorphous complexes independent of the nature of the halide.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 619-624  [ doi:10.1107/S0108768112043972 ]

Hydrothermal synthesis and crystal structure of novel bis(6-carboxypyridine-2-carboxylato-³O²,N,O⁶)nickel(II) trihydrate, Ni(Hpydc)₂·3H₂O

S. Sanotra, R. Gupta, H. N. Sheikh, B. L. Kalsotra, V. K. Gupta and Rajnikant

Synopsis: The title compound Ni(Hpydc)₂·3H₂O is found to form a porous metal-organic framework (MOF) structure. Nickel ions are coordinated by two tridentate ionic organic ligands. The framework is completed by multiple hydrogen bonds between organic moieties.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 625-635  [ doi:10.1107/S0108768112040724 ]

Charge-density distribution in potassium dihydrogen phosphoglycolate - a comparison of phosphate and phosphonate groups

A. Mermer and P. Starynowicz

Synopsis: Charge-density distribution in potassium dihydrogen phosphoglycolate, K(HO₃POCH₂COOH), has been studied experimentally and by density-functional theory (DFT) calculations; the results have been compared with simple phosphonates.

Online 23 October 2012

 

Acta Cryst. (2012). B68, 636-645  [ doi:10.1107/S0108768112037184 ]

The first report of the crystal structure of non-solvated -oxo boron subphthalocyanine and the crystal structures of two solvated forms

M. V. Fulford, A. J. Lough and T. P. Bender

Synopsis: The oxygen-bridged dimer of boron subphthalocyanine [-oxo-(BsubPc)₂] has been crystallized in solvated form and, by sublimation, in solvent-free form. The arrangement of the complexes in the solvent-free crystals is essentially different from the arrangement in solvated crystals.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 646-660  [ doi:10.1107/S0108768112042826 ]

Experimental and database-transferred electron-density analysis and evaluation of electrostatic forces in coumarin-102 dye

Y. Bibila Mayaya Bisseyou, N. Bouhmaida, B. Guillot, C. Lecomte, N. Lugan, N. Ghermani and C. Jelsch

Synopsis: The multipolar charge density of a new polymorph of coumarin-102 was determined experimentally and compared with that obtained through a database transfer approach. Atomic charges as well as total and interatomic electrostatic forces were computed based on the electric field and Maxwell tensor flux through atomic basin surfaces.

Online 16 November 2012

 

Acta Cryst. (2012). B68, 661-666  [ doi:10.1107/S0108768112036191 ]

Structures of four polymorphs of the pesticide dithianon solved from X-ray powder diffraction data

I. Halasz, R. Dinnebier, T. Chiodo and H. Saxell

Synopsis: The crystal structures of four polymorphs of the pesticide dithianon with Z' from 1 to 3 were elucidated by laboratory X-ray powder diffraction. Three polymorphs crystallize in non-centrosymmetric space groups and molecules pack via weak interactions between quinoid moieties.

Online 23 October 2012

 

Acta Cryst. (2012). B68, 667-676  [ doi:10.1107/S0108768112039651 ]

Solvatomorphism of 9,9'-[1,3,4-thiadiazole-2,5-diylbis(2,3-thiophendiyl-4,1-phenylene)]bis[9H-carbazole]: isostructurality, modularity and order-disorder theory

B. Stöger, P. Kautny, D. Lumpi, E. Zobetz and J. Fröhlich

Synopsis: The structural relationships of six solvates of 9,9'-[1,3,4-thiadiazole-2,5-diylbis(2,3-thiophendiyl-4,1-phenylene)]bis[9H-carbazole] are analyzed using the concepts of isostructurality, modularity and polytypism.

Online 23 October 2012

 

Acta Cryst. (2012). B68, 677-685  [ doi:10.1107/S0108768112045636 ]

The polymorphs of ROY: application of a systematic crystal structure prediction technique

M. Vasileiadis, A. V. Kazantsev, P. G. Karamertzanis, C. S. Adjiman and C. C. Pantelides

Synopsis: A systematic methodology for crystal structure prediction is shown to successfully identify the seven known polymorphs of 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, also known as ROY, five of which are within the 12 lowest energy structures.

Online 16 November 2012