Showing papers by "Enrique J. Baran published in 2016"
TL;DR: In this paper, the structure of PO3F tetrahedra and polyhedral polyhedra was shown to collapse along [100] from a layered arrangement into a framework structure, accompanied by a change of coordination number of the Sr2+ ions from eight to nine.
Abstract: Single crystals of Sr(PO3F)·H2O {P21/c, Z = 4, a = 7.4844(2) A, b = 7.0793(2) A, c = 8.4265(2) A, β = 108.696(1)°, V = 422.91(2) A3, 2391 Fo2, 70 parameters, R1[F2 > 2σ(F2)] = 0.036; wR2(F2 all) = 0.049, S = 1.054} were grown from an aqueous solution by a metathesis reaction. The structure comprises [SrO8] polyhedra and PO3F tetrahedra that form a layered arrangement parallel to (100). The topotactic dehydration of this phase proceeds between 80 and 140 °C to afford Sr(PO3F). The monazite-type crystal structure of Sr(PO3F) was elucidated from the X-ray powder data by simulated annealing [P21/c, Z = 4, a = 6.71689(9) A, b = 7.11774(11) A, c = 8.66997(13) A, β = 128.0063(7)°, V = 326.605(8) A3, Rp = 0.010, Rwp = 0.015, RF = 0.030]. During dehydration, the structure of Sr(PO3F)·H2O collapses along [100] from a layered arrangement into a framework structure, accompanied by a change of the coordination number of the Sr2+ ions from eight to nine. The magic-angle spinning (MAS) NMR and vibrational spectroscopy data of both phases are discussed.
13 citations
TL;DR: In this article, a review of synthetic oxalato-complexes analogous to these natural species, including usual synthetic procedures and a thorough analysis of their crystallographic and structural peculiarities is presented.
Abstract: Four iron-containing natural oxalates, usually classified as organic minerals, are known (humboldtine, minguzzite, stepanovite and zhemchuzhnikovite). Their occurrences and general properties are presented and briefly discussed. The subsequent part of the review is devoted to the discussion of synthetic oxalato-complexes, analogous to these natural species, including usual synthetic procedures and a thorough analysis of their crystallographic and structural peculiarities. The thermal, spectroscopic and magnetic properties of these complexes are also analyzed in detail and comparisons with other closely related complexes are also included in the discussions.
12 citations
03 Feb 2016
TL;DR: Piro, Oscar Enrique as discussed by the authors, et al. as discussed by the authors presented a model of the Instituto de Fisica La Plata (IFLP) in the context of the Consejo Nacional de Investigaciones Cientificas y Tecnicas.
Abstract: Fil: Piro, Oscar Enrique. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata. Instituto de Fisica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Fisica La Plata; Argentina
12 citations
TL;DR: Piro, Oscar Enrique as mentioned in this paper, et al. as mentioned in this paper presented a model of the Instituto de Fisica La Plata (IFLP) in the context of the Consejo Nacional de Investigaciones Cientificas y Tecnicas.
Abstract: Fil: Piro, Oscar Enrique. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata. Instituto de Fisica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Fisica La Plata; Argentina
8 citations
TL;DR: Torres et al. as discussed by the authors presented a study on the Patagonia Austral region and its relationship with the University of Nacional de la Patagonía Austral (Unidad Academica Rio Gallegos).
Abstract: Fil: Torres, Maria Marta. Universidad Nacional de la Patagonia Austral. Unidad Academica Rio Gallegos; Argentina
4 citations
TL;DR: In this article, a new general synthetic procedure for preparation of Na3[Fe(C2O4)3]·5H2O (1), Rb3[ Fe(C 2O4]·3H 2O (2), and Cs3[F2O 4]·2H 2 O (3) was developed.
Abstract: A new general synthetic procedure for preparation of Na3[Fe(C2O4)3]·5H2O (1), Rb3[Fe(C2O4)3]·3H2O (2), and Cs3[Fe(C2O4)3]·2H2O (3) was developed. The crystal structures of these salts have been determined by single crystal X-ray diffraction. Salt 1 crystallizes in the monoclinic space group C2/c with Z = 8, salt 2 in P21/c with Z = 4, and salt 3 in P21/n with Z = 4. The three new salts and K3[Fe(C2O4)3]·3H2O, prepared for comparative purposes, were further characterized by infrared and 57Fe-Mossbauer spectroscopy. These spectra are discussed in comparison with those of related oxalato complexes.
3 citations
Journal Article•
TL;DR: The mean amplitudes of vibration of XeOF2, a new example of a Xe(IV) compound, were calculated from recently reported spectroscopic and structural data in the temperature range between 0 and 500 K as discussed by the authors.
Abstract: The mean amplitudes of vibration of XeOF2, a new example of a Xe(IV) compound, were calculated from recently reported spectroscopic and structural data in the temperature range between 0 and 500 K. The results are compared with those of related species and the bond peculiarities of the molecule are also briefly discussed. Its thermodynamic functions were also determined, using the rigid rotator/harmonic oscillator approximation.
1 citations