0000000000349971

AUTHOR

Juan Rodríguez-carvajal

0000-0001-5582-2632

Neutron diffraction studies of the molecular compound [Co 2(bta)]n (H4bta =1,2,4,5-benzenetetracarboxylic acid): In the quest of canted ferromagnetism

The exchange mechanism and magnetic structure of the organic-inorganic layered molecule-based magnet [Co2(bta)]n (1) (H 4bta =1,2,4,5-benzenetetracarboxylic acid) have been investigated through variable-temperature magnetic susceptibility measurements and supported with a series of neutron diffraction experiments. Cryomagnetic studies have shown an antiferromagnetic ordering at a transition temperature of 16 K that is followed by the appearance of a weak ferromagnetism below 11 K. The weak antiferromagnetic interlayer interaction plays an important role in this system in spite of the long interlayer separation. A ferromagnetic ordering is induced by applied magnetic fields greater than 1800…

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The Role of Order-Disorder Transitions in the Quest for Molecular Multiferroics: Structural and Magnetic Neutron Studies of a Mixed Valence Iron (II)-Iron (III) Formate Framework

Neutron diffraction studies have been carried out to shed light on the unprecedented order-disorder phase transition (ca. 155 K) observed in the mixed-valence iron(II)-iron(III) formate framework compound [NH 2(CH3)2]n[FeIIIFe II(HCOO)6]n. The crystal structure at 220 K was first determined from Laue diffraction data, then a second refinement at 175 K and the crystal structure determination in the low temperature phase at 45 K were done with data from the monochromatic high resolution single crystal diffractometer D19. The 45 K nuclear structure reveals that the phase transition is associated with the order-disorder of the dimethylammonium counterion that is weakly anchored in the cavities …

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Synthesis, crystal structure, and magnetic characterization of the three-dimensional compound [Co2(cbut)(H2O) 3]n (H4cbut = 1,2,3,4- cyclobutanetetracarboxylic acid)

A novel cobalt(II) complex of formula [Co2(cbut)(H 2O)3]n (1) (H4cbut = 1,2,3,4-cyclobutanetetracarboxylic acid) has been synthesized under hydrothermal conditions and its crystal structure has been determined by means of synchrotron radiation and neutron powder diffraction. The crystal structure of 1 consists of layers of cobalt(II) ions extending in the bc-plane which are pillared along the crystallographic a-axis through the skeleton of the cbut 4- ligand. Three crystallographically independent cobalt(II) ions [Co(1), Co(2), and Co(3)] occur in 1. They are all six-coordinate with four carboxylate-oxygens [Co(1)-Co(3)] and two cis-[Co(1)] or trans-water molecules [Co(2) and Co(3)] buildin…

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Experimental and Theoretical Study of SbPO 4 under Compression

SbPO4 is a complex monoclinic layered material characterized by a strong activity of the non-bonding lone electron pair (LEP) of Sb. The strong cation LEP leads to the formation of layers piled up along the a-axis and linked by weak Sb-O electrostatic interactions. In fact, Sb is 4-fold coordination with O similar to what occurs with the P-O coordination, despite the large difference of ionic radii and electronegativity between both elements. Here we report a joint experimental and theoretical study of the structural and vibrational properties of SbPO4 at high pressure. We show that SbPO4 is not only one of the most compressible phosphates but also one of the most compressible compounds of …

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CCDC 983489: Experimental Crystal Structure Determination

Related Article: Pau Díaz-Gallifa, Oscar Fabelo, Jorge Pasán, Laura Cañadillas-Delgado, Juan Rodríguez-Carvajal, Francesc Lloret, Miguel Julve, and Catalina Ruiz-Pérez|2014|Inorg.Chem.|53|5674|doi:10.1021/ic500443t

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CCDC 945084: Experimental Crystal Structure Determination

Related Article: Laura Cañadillas-Delgado , Oscar Fabelo , J. Alberto Rodríguez-Velamazán , Marie-Hélène Lemée-Cailleau , Sax A. Mason , Emilio Pardo , Francesc Lloret , Jiong-Peng Zhao , Xian-He Bu , Virginie Simonet , Claire V. Colin , and Juan Rodríguez-Carvajal|2012|J.Am.Chem.Soc.|134|19772|doi:10.1021/ja3082457

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CCDC 945083: Experimental Crystal Structure Determination

Related Article: Laura Cañadillas-Delgado , Oscar Fabelo , J. Alberto Rodríguez-Velamazán , Marie-Hélène Lemée-Cailleau , Sax A. Mason , Emilio Pardo , Francesc Lloret , Jiong-Peng Zhao , Xian-He Bu , Virginie Simonet , Claire V. Colin , and Juan Rodríguez-Carvajal|2012|J.Am.Chem.Soc.|134|19772|doi:10.1021/ja3082457

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CCDC 952343: Experimental Crystal Structure Determination

Related Article: Oscar Fabelo, Laura Cañadillas-Delgado, Jorge Pasán, Pau Díaz-Gallifa, Catalina Ruiz-Pérez, Francesc Lloret, Miguel Julve, Inés Puente Orench, Javier Campo, and Juan Rodríguez-Carvajal|2013|Inorg.Chem.|52|12818|doi:10.1021/ic402186p

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CCDC 945082: Experimental Crystal Structure Determination

Related Article: Laura Cañadillas-Delgado , Oscar Fabelo , J. Alberto Rodríguez-Velamazán , Marie-Hélène Lemée-Cailleau , Sax A. Mason , Emilio Pardo , Francesc Lloret , Jiong-Peng Zhao , Xian-He Bu , Virginie Simonet , Claire V. Colin , and Juan Rodríguez-Carvajal|2012|J.Am.Chem.Soc.|134|19772|doi:10.1021/ja3082457

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