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Acta Cryst. (2014). A70, C1295
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The Mexican Society of Crystallography (SMCr) has 19 years old; 14 Regional Delegations (red points in the map below); has celebrated six national meetings (each one with audiences of around 250, red points with circles in the map below); and several courses, workshops, conferences along its lifespan. Also around 50 monographs have been produced, with some videos, games and souvenirs related with crystallography. A lot of them have been designed for improving the teaching of crystallography in graduate and postgraduate programs. Visits to the giant crystals of gypsum in the locality of Naica in the mexican state of Chihuahua, were organized by the SMCr with the kindly permission of Peñoles Company. Documents concerning to the history of crystallography in Mexico have been published by A. Cordero-Borboa [1-3]. On 2014, the SMCr will celebrate the IYCr,with organizing several activities and its seventh national meeting. With other Latin American countries will join to the initiative of found the Latin American Crystallographic Association (LACA) and its incorporation as Regional Associate of the International Union of Crystallography (IUCr). In the next images, circling the map of Mexico, starting from the upper left and following clockwise sense: cave of swords; gem (workshop on gemology); giant crystals of gypsum in Naica; crystal drawings (mineralogy for kids workshop); workshop on the Rietveld method; mineralogy for kids workshop; workshop on crystal growth of proteins.

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Acta Cryst. (2014). A70, C1763
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Structural models for the new layered germanates ScInGe2O7 and ScFeGe2O7 were analyzed within the framework of symmetry relations between space groups. These compounds were supposed to be hettotypes of the thortveitite mineral, (Sc,Y)2Si2O7, which was considered as the aristotype. Thortveitite crystallizes in the monoclinic system, and the symmetry is described by the space group type C2/m. Other monoclinic hettotypes for the thortveitite are FeInGe2O7 (PDF 01-070-8447, ICSD - 94487), space group C2/m (No. 12); TbInGe2O7 (PDF 01-072-6515, ICSD - 96360), space group C2/c (No. 15); and FeYGe2O7 (PDF 01-072-6099, ICSD - 95935), space group P21/m (No. 11). All these space groups are related by symmetry. By the use of these relations, we proposed starting models for the crystal structures of ScInGe2O7 and ScFeGe2O7. For ScInGe2O7 this was found to be isostructural to FeInGe2O7 reported by our laboratory [1]. The structural data for this compound were obtained by conventional Rietveld refinement of the powder diffraction data of X-rays, using the GSAS program and EXPGUI [2, 3] interface. For ScFeGe2O7 the symmetry related structural model was found in the triclinic system by symmetry reduction from the space group C2/m (unique axis b) to the triclinic space group P1 (figure 1). Rietveld refinement was performed reaching to the following results: lattice parameters a = 5.3434 (8), b = 5.3145 (8), c = 4.8732 (7 ) Å, α = 99 468 (2), β = 97 257 (2), γ = 104 609 (2) 0, V = 130.03 (5) A3, Z = 1; WRp = 0.047, Rp = 0.04 and reduced χ2 of 2.176 for 64 variables. This study was sponsored by CONACyT project CB-2011/167624.
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