... JA Barth, Leipzig Mixed Halide Tin( IV) Complexes with NN-Dimethylformamide and Dimethylsulfo... more ... JA Barth, Leipzig Mixed Halide Tin( IV) Complexes with NN-Dimethylformamide and Dimethylsulfoxide DAVID TUDELA, VICENTE FERNANDEZ Madrid (Spain), Departamento de Quimica InorgiLnica, Facultad de Ciencias, Universidad Atbnoma JESUS D. TORNERO ...
Acta Crystallographica Section C Crystal Structure Communications
PALLADIUM pyrazole rings. The two planes in the dimer are parallel to each other, but the second ... more PALLADIUM pyrazole rings. The two planes in the dimer are parallel to each other, but the second plane rotates about the Pd(1)-Pd(2) vector relative to the first by 39-3 ° leading to a staggered conformation. The rotation appears necessary for hydrogen bonding, in addition to the reduction of steric hindrance among the intermolecular ligands. As a consequence of the hydrogen bonds, all the N-H groups lie between the two planes, although such an arrangement would somewhat raise the repulsion between intermolecular pyrazole ligands. All four Pd-C1 bonds are equivalent within experimental error, as are the Pd-N bonds. These bond lengths are comparable with the reported values for Pd-C1 of 2.297 (1)A and for Pd-N of 2.030 (3) A in [Pd{(CH3)2C(C3H3N2)2}C12] (Minghetti, Cinellu, Bandini, BanditeUi, Demartin & Manassero, 1986).
The enhancement of active triggered by surface deposition of Cu, Bi, and Ce containing oxidic spe... more The enhancement of active triggered by surface deposition of Cu, Bi, and Ce containing oxidic species onto a high surface area anatase is analyzed through the calculation of the quantum efficiency for toluene photodegradation under UV and Sunlight-type illumination. To this end, series of Cu, Bi, and Ce containing oxides supported on anatase were synthesized having a growing content of the Cu, Bi, and Ce surface species and characterized with X-ray diffraction and photoelectron, UV-visible, and photoluminescence spectroscopies as well as transmission electron microscopy. Utilizing the surface concentration of Cu, Bi, and Ce species as a tool, we analyzed the influence of the system physicochemical properties affecting quantum efficiency in anatase-based materials. First, employing small surface concentrations of the Cu, Bi, and Ce species deposited onto (the unperturbed) anatase, we provided evidence that all steps of the photocatalytic event, including light absorption, charge reco...
The reaction of SnMe 2 Br 2 with Et 4 NBr, in a 1:2 molar ratio, yields (Et 4 N) 2 [SnMe 2 Br 4 ]... more The reaction of SnMe 2 Br 2 with Et 4 NBr, in a 1:2 molar ratio, yields (Et 4 N) 2 [SnMe 2 Br 4 ] (1) in CHCl 3 /hexane mixtures but (Et 4 N)[SnMe 2 Br 3 ] (2) in water. This remarkable solvent dependence is explained by means of a thermochemical cycle that includes the lattice ...
The relationship between the Mossbauer partial quadrupole splitting (pqs) of the ligands and the ... more The relationship between the Mossbauer partial quadrupole splitting (pqs) of the ligands and the crystallographic Sri-Cl distances, has been studied for [SnC15L]' complexes. While the Sri-Cl distance trans to L is not very sensitive to the nature of the ligand, the Sri-Cl distances cis to L and the average Sri-Cl distance decrease linearly for increasing values of pqs(L). The slopes of the plots d(Sn-Cl) vs 4pqs for SnC14L2 and [SnCl ratio 25:l expecte a Ll-complexes, are in the ratio 2.6(3):1, in good agreement with the on the basis that in SnC14L2 there are 2 L groups for 4 Cl atoms, while in [SnC15L]-there is only one L group for 5 Cl atoms. For the isoelectronic SbClsL complexes, the Sb-Cl bond distances are also linearly related to the 121-Sb quadrupole coupling constants. Therefore, both 121-Sb Mijssbauer and NQR spectra can be used to predict Sb-Cl distances.
Thermodynamic information is critical for the assessment of the reactivity and stability of mater... more Thermodynamic information is critical for the assessment of the reactivity and stability of materials. New procedures have recently been developed that provide straightforward predictive methods for estimating lattice energy and standard entropy of conventional salts. These procedures also open up new possibilities for estimating the thermochemistry involving salts for which there is little or no structural information available, as well as for conventional, well-characterized, ionic materials. These approaches are based on volume data, obtained from crystal structure determinations or from additive single-ion volume data (or estimates thereof), or on experimental densities. A detailed example explains the observed trend in increasing stability of bisulfites as the size of the cation increases and shows how quantitative free energy information can be obtained. Errors are also discussed.
Journal of the Chemical Society Chemical Communications
... David Tudela,a* Masood A. Khan,b and Jerold J. Zuckermanbt a Departamento de Quimica, Univers... more ... David Tudela,a* Masood A. Khan,b and Jerold J. Zuckermanbt a Departamento de Quimica, Universidad Autonoma de Madrid, 28049 Madrid, Spain b Department of Chemistry, The University of Oklahoma, Norman, OK 73019 ... G. Valle, P. WC Barnard, and J. D. Donaldson, Inorg ...
... JA Barth, Leipzig Mixed Halide Tin( IV) Complexes with NN-Dimethylformamide and Dimethylsulfo... more ... JA Barth, Leipzig Mixed Halide Tin( IV) Complexes with NN-Dimethylformamide and Dimethylsulfoxide DAVID TUDELA, VICENTE FERNANDEZ Madrid (Spain), Departamento de Quimica InorgiLnica, Facultad de Ciencias, Universidad Atbnoma JESUS D. TORNERO ...
Acta Crystallographica Section C Crystal Structure Communications
PALLADIUM pyrazole rings. The two planes in the dimer are parallel to each other, but the second ... more PALLADIUM pyrazole rings. The two planes in the dimer are parallel to each other, but the second plane rotates about the Pd(1)-Pd(2) vector relative to the first by 39-3 ° leading to a staggered conformation. The rotation appears necessary for hydrogen bonding, in addition to the reduction of steric hindrance among the intermolecular ligands. As a consequence of the hydrogen bonds, all the N-H groups lie between the two planes, although such an arrangement would somewhat raise the repulsion between intermolecular pyrazole ligands. All four Pd-C1 bonds are equivalent within experimental error, as are the Pd-N bonds. These bond lengths are comparable with the reported values for Pd-C1 of 2.297 (1)A and for Pd-N of 2.030 (3) A in [Pd{(CH3)2C(C3H3N2)2}C12] (Minghetti, Cinellu, Bandini, BanditeUi, Demartin & Manassero, 1986).
The enhancement of active triggered by surface deposition of Cu, Bi, and Ce containing oxidic spe... more The enhancement of active triggered by surface deposition of Cu, Bi, and Ce containing oxidic species onto a high surface area anatase is analyzed through the calculation of the quantum efficiency for toluene photodegradation under UV and Sunlight-type illumination. To this end, series of Cu, Bi, and Ce containing oxides supported on anatase were synthesized having a growing content of the Cu, Bi, and Ce surface species and characterized with X-ray diffraction and photoelectron, UV-visible, and photoluminescence spectroscopies as well as transmission electron microscopy. Utilizing the surface concentration of Cu, Bi, and Ce species as a tool, we analyzed the influence of the system physicochemical properties affecting quantum efficiency in anatase-based materials. First, employing small surface concentrations of the Cu, Bi, and Ce species deposited onto (the unperturbed) anatase, we provided evidence that all steps of the photocatalytic event, including light absorption, charge reco...
The reaction of SnMe 2 Br 2 with Et 4 NBr, in a 1:2 molar ratio, yields (Et 4 N) 2 [SnMe 2 Br 4 ]... more The reaction of SnMe 2 Br 2 with Et 4 NBr, in a 1:2 molar ratio, yields (Et 4 N) 2 [SnMe 2 Br 4 ] (1) in CHCl 3 /hexane mixtures but (Et 4 N)[SnMe 2 Br 3 ] (2) in water. This remarkable solvent dependence is explained by means of a thermochemical cycle that includes the lattice ...
The relationship between the Mossbauer partial quadrupole splitting (pqs) of the ligands and the ... more The relationship between the Mossbauer partial quadrupole splitting (pqs) of the ligands and the crystallographic Sri-Cl distances, has been studied for [SnC15L]' complexes. While the Sri-Cl distance trans to L is not very sensitive to the nature of the ligand, the Sri-Cl distances cis to L and the average Sri-Cl distance decrease linearly for increasing values of pqs(L). The slopes of the plots d(Sn-Cl) vs 4pqs for SnC14L2 and [SnCl ratio 25:l expecte a Ll-complexes, are in the ratio 2.6(3):1, in good agreement with the on the basis that in SnC14L2 there are 2 L groups for 4 Cl atoms, while in [SnC15L]-there is only one L group for 5 Cl atoms. For the isoelectronic SbClsL complexes, the Sb-Cl bond distances are also linearly related to the 121-Sb quadrupole coupling constants. Therefore, both 121-Sb Mijssbauer and NQR spectra can be used to predict Sb-Cl distances.
Thermodynamic information is critical for the assessment of the reactivity and stability of mater... more Thermodynamic information is critical for the assessment of the reactivity and stability of materials. New procedures have recently been developed that provide straightforward predictive methods for estimating lattice energy and standard entropy of conventional salts. These procedures also open up new possibilities for estimating the thermochemistry involving salts for which there is little or no structural information available, as well as for conventional, well-characterized, ionic materials. These approaches are based on volume data, obtained from crystal structure determinations or from additive single-ion volume data (or estimates thereof), or on experimental densities. A detailed example explains the observed trend in increasing stability of bisulfites as the size of the cation increases and shows how quantitative free energy information can be obtained. Errors are also discussed.
Journal of the Chemical Society Chemical Communications
... David Tudela,a* Masood A. Khan,b and Jerold J. Zuckermanbt a Departamento de Quimica, Univers... more ... David Tudela,a* Masood A. Khan,b and Jerold J. Zuckermanbt a Departamento de Quimica, Universidad Autonoma de Madrid, 28049 Madrid, Spain b Department of Chemistry, The University of Oklahoma, Norman, OK 73019 ... G. Valle, P. WC Barnard, and J. D. Donaldson, Inorg ...
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